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PROF.  CHARLES  A.  KOFOID  AND 
MRS.  PRUDENCE  W.  KOFOID 


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osr 

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AND 

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ED.   BARRINGTON  &   GEO.    D.   HASWELL, 

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The  London  Dissector,  revised  by  E.  J.  Chaisty,  M.D.,  Baltimore.   From 
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THE 

LONDON    DISSECTOR, 


OR 


GUIDE  TO  ANATOMY; 

FOR    THE    USE    OP    STUDENTS: 


COMPRISING 

A   DESCRIPTION    OF    THE    MUSCLES,  VESSELS,  NERVES,  LYMPHATICS, 

AND    VISCERA    OF    THE    HUMAN    BODT,  AS    THEY 

APPEAR    ON    DISSECTION  J 


WITH   DIRECTIONS    FOR   THEIR   DEMONSTRATION. 


FROM   THE   LAST   LONDON   EDITION. 


REVISED    AND    CORRECTED    BY 

EDWARD    J.    C  H  A  I  S  T  Y,    M.  D., 

LATE  DEMONSTRATOR   OF  ANATOMY   IN  THE   UNIVERSITY   OF  MARYLAND. 


PHILADELPHIA : 

ED.  HARRINGTON  &  GEO.  D.  HAS  WELL. 
1842. 


Entered,  according  to  the  Act  of  Congress,  in  the  year  eighteen  hundred  and 
thirty-nine,  by  JOHN  MORPHY,  in  the  Clerk's  Office  of  the  District  Court 
of  Maryland. 


x-X      .  ^          I 


PREFACE. 


IN  presenting  the  LONDON  DISSECTOR,  under  its 
present  form,  to  the  American  Student,  it  may  be 
proper  to  remark,  that  I  have  been  prompted  by  no 
feelings  of  vanity;  no  eagerness  for  authorship.  I 
felt,  even  in  my  own  period  of  study,  the  difficulty  of 
procuring  brief  and  satisfactory  guides  for  the  student 
of  anatomy:  I  perceived  with  what  reluctance  he 
perused  the  larger  works  intended  to  direct  him  in 
his  dissection;  how  rapidly  he  hurried  over  the  lengthy 
description  of  the  various  parts,  and  I  was  led  to 
believe,  that  a  short  and  sufficiently  extensive  manual, 
would  be  welcomed  as  a  desideratum  by  the  young 
dissector.  Believing,  that  with  a  few  alterations  and 
additions,  the  London  Dissector  might  easily  be 
transformed  into  a  work  of  this  description,  I  have 
been  induced  to  undertake  the  task. 


VH1  PREFACE. 

It  is  but  just,  however,  to  acknowledge,  that  for 
these  additions  I  have  been  indebted  to  authors  of 
well  known  celebrity;  that  I  have  drawn  freely  from 
Bell's  admirable  treatise  on  Anatomy;  and  Shaw's 
excellent  work  on  Dissection;  and  that  should  the 
present  volume  be  still  received  as  a  work  of  merit, 
the  praise  must  redound  to  the  original  author  of  the 
work,  not  to  the  compiler.  His  labor  will  be  amply 
compensated,  if  it  but  facilitate  the  progress  of  the 
student,  in  the  acquisition  of  anatomical  knowledge. 


CONTENTS. 


PART  I.  — THE  MUSCULAR  SYSTEM. 

Page. 

GENERAL  RULES  FOR  DISSECTION, 13 

CHAPTER  I.— Dissection  of  the  Abdomen, 15 

-Section  I.— Muscles  of  the  Abdomen, 15 

See.  II. — Description  of  the  Anatomy  of  the  Parts  connected  with 

Hernia, x  .  .  23 

Sec.  III.— Dissection  of  the  Cavity  of  the  Abdomen,  ...  39 
CHAP.  II. — Dissection  of  the  Perineum  and  Organs  of  Generation 

in  the  Male, 51 

CHAP.  III. — Dissection  of  the  Organs  of  Generation  in  the  Female,  59 

CHAP.  IV.— Dissection  of  the  Thigh, ,66 

Sec.  I.— Of  the  Anterior  Part  of  the  Thigh,  .  ;..'---% '^  .  66 

Sec.  II.— Of  the  "Posterior  Part  of  the  Thigh,  ....  72 

CHAP.  V.— Dissection  of  the  Leg  and  Foot,  ....  78 

Sec.  I.— Of  the  Fore  Part  of  the  Leg  and  Foot,  .  ...  78 

Sec.  II.— Dissection  of  the  Posterior  Part  of  the  Leg,  .  .  84 

Sec.  III.— Dissection  of  the  Sole  of  the  Foot,  ....  88 

CHAP.  VI.— Dissection  of  the  Upper  Part  of  the  Body,  .  .  93 

Sec.  I.— Of  the  External  Parts  of  the  Head,  .  .  .  .  93 
Sec.  II.— Of  the  Contents  of  the  Cranium,  or  of  the  Brain  and  its 

Membranes, 97 

CHAP.  VII.— Dissection  of  the  Anterior  Part  of  the  Neck,  .  115 

CHAP.  VIII.— Dissection  of  the  Muscles  on  the  outside  of  the  . 

Thorax,     .        .        .  122 


X  CONTENTS. 

Pa$e. 

Of  the  Parts  within  the  Thorax,      .        .        .        .,     .        .      124 

Dissection  of  the  Heart,  when  removed  from  the  Body,      .        .      128 
CHAP.IX.— Dissection  of  the  Muscles  of  the  Face,     .        ...       .      131 

CHAP.  X.— Dissection  of  the  Throat,      ".       \       ...      139 
The  Muscles  situated  about  the  entry  of  the  Fauces,      .        .      140 
Muscles  on  the  Back  Part  of  the  Pharynx,      .        . '      v*....      142 

Muscles  of  the  Larynx,    .        ....        .        .        I  •<  '.      143 

CHAP.  XL— Dissection  of  the  Orbit  of  the  Eye,          .      ^i  -  -   .      146 
Muscles  situated  within  the  Orbit,  .        .  -n ..». •-- -( •,.&* .-.      -^      146 
CHAP.  XIL— Dissection  of  the  Muscles  on  the  Posterior  Part  of  the 

Trunk  and  Neck, .149 

CHAP.  XIIL— Dissection  of  the  Muscles  situated  between  the  Ribs, 

and  on  the  inner  Surface  of  the  Sternum,  .  .•••,    ...  -v  >^.      162 
CHAP.  XIV. — Dissection  of  the  Muscles  situated  on  the  anterior 

part  of  the  Neck,  close  to  the  Vertebrae,   .        .        .        .164 
CHAP.  XV.— Dissection  of  the  Superior  Extremity ,'  .        .        .       166 

Sec.  I.— Of  the  Shoulder  and  Arm, 166 

Sec.  II. — Dissection  of  the  Fascia  and  Muscles  situated  on  the 

Cubit  or  Fore  Arm, ;•*>'.      171 

Sec.  III.— Dissection  of  the  Palm  of  the  Hand,    .        .        .        ,      182 


PART  II.— THE  VASCULAR  AND  NERVOUS  SYSTEMS,  189 

Of  the  Vessels  and  Nerves  situated  behind  the  Peritoneum,  .  190 
Of  the  Vessels  and  Nerves  contained  within  the  Pelvis,  .  .197 
Of  the  Vessels  and  Nerves  on  the  Fore  Part  and  Inside  of  the 

Thigh,    .  m  ^  :..• .   .     :  /#&  :»r- r  .--".  -    .    200 

Of  the  Vessels  and  Nerves  on  the  Posterior  part  of  the  Thigh,  203 
Of  the  Vessels  and  Nerves  situated  on  the  Fore  part  of  the 

Leg  and  Foot,    .        .       ;^.^fVi^/       .-V:    p£-#£1          207 
Vessels  and  Nerves  of  the  Posterior  part  of  the  Leg,       .        .209 


CONTENTS.  XJ 

Page. 

Of  the  Vessels  of  the  Brain, 212 

Of  the  Vessels  and  Nerves  seen  in  the  Dissection  of  the  Neck,  213 
The  course  of  the  Subclavian  Artery  and  its  Branches,  on  each 

side,          .  '  .        .        .        .        .        .        .        .      222 

The  course  of  the  Brachial  Plexus  of  Nerves,  .        .        .        .224 

The  Dissection  of  the  Axilla,  or  Arm-  Pit,        ....      224 

Dissection  of  the  Posterior  Mediastinum,  and  of  the  Nerves  and 

Vessels  which  have  their  course  through  the  Thorax,  .  228 
Branches  of  the  Intercostal  in  the  Thorax,  ....  229 

Of  the  Vessels  and  Nerves  of  the  Face, 233 

Of  the  Vessels  and  Nerves  met  with  in  the  Orbit  of  the  Eye,  238 
The  Dissection  of  the  Cutaneous  Vessels  and  Nerves  of  the 

Shoulder  and  Arm 240 

Of  the  Vessels  and  Nerves  of  the.  Superior  Extremity,  .  .  243 
The  Method  of  Injecting  the  Arteries,  .....  252 
The  Method  of  Injectingthe  Heart,  .  .  .  .  .253 

The  Lymphatic  or  Absorbent  System, 256 

Of  the  course  of  the  Lymphatics,  .  .  .,  .  .  .  257 
Directions  for  making  Lymphatic  Preparations,  .  .  .  270 


COMPENDIUM 


PRACTICAL  ANATOMY 


GENERAL    RULES    FOR    DISSECTION. 

DEXTERITY  in  the  manual  operation  of  dissection 
can  be  acquired  only  by  practice;  the  observance, 
however,  of  certain  general  rules  will  facilitate  the 
labor  of  the  student. 

1.  The  position  of  the  hand  in  dissecting  should 
be  the  same  as  in  writing  or  drawing;  and  the  knife, 
held,  like  the  pen  or  pencil,  by  the  thumb  and  the 
first  two  fingers,  should  be  moved  by  means  of  them 
only;  the  hand  resting  firmly  on  the  two  other  fingers 
bent  inwards,  as  in  writing,  and  on  the  wrist.  The 
instrument  can  thus  be  guided  with  much  more 
steadiness  and  precision,  than  when  moved  by  means 
of  the  wrist,  elbow,  or  shoulder. 

1  2.  No  more  of  the  integuments  should  at  any  time  be 
removed,  than  is  necessary  for  the  present  dissection,  as 
exposure  to  the  air  renders  the  parts  dry  and  indistinct. 

3.  In  dissecting  muscular  parts,  the  muscles  should 
be  extended;  the  cellular  membrane  which  connects 
them  to  the  integuments  should  be  placed  on  the 
stretch,  and  entirely  removed  with  the  skin;  the 
knife  should  be  kept  close  to  the  muscles,  and  carried 
steadily  in  the  direction  of  their  fibres,  separating  a 
fasciculus  at  each  stroke: — thus  the  exposed  surface 
will  appear  clean,  and  the  course  of  the  fibres  distinct, 
2 


14  GENERAL  RULES  FOR  DISSECTION. 

4.  When  small  vessels  are  are  to  be  demonstrated, 
another  method  is  to  be  followed;  the  skin  only  must 
be  removed,  and  the  cellular  membrane  cautiously 
dissected  from  the  vessels. 

5.  During  dissection,  every  little  operation  should 
be  practised,  which  can  give  the  dexterity  of  hand 
so  essential  to  the  surgeon:  such  as  the  use  of  the 
catheter  and  probang,  the  introduction   of  a  probe 

,  through  the  nose  into  the  Eustachian  tube,  or  nasal 
duct,  and  the  cutting  down  to  the  various  arteries 
which  may  become  the  object  of  surgical  operations: 
as  the  external  iliac,  femoral,  anterior  and  posterior 
tibial,  brachial,  radial,  and  ulnar,  &c. 

The  grand  object  of  the  surgical  student  is  to 
acquire  a  knowledge  of  the  relative  situation  of  parts. 
This  should  be  kept  in  view  in  all  his  anatomical 
labors.  Hence,  when  he  is  dissecting  the  muscles, 
he  should  carefully  expose  the  chief  blood-vessels 
and  nerves,  and  attentively  consider  their  position 
with  regard  to  each  other,  and  to  the  surrounding 
parts.  The  smaller  arteries  and  veins,  and  the  mi- 
nute nervous  ramifications,  will  be  more  advantage- 
ously studied  on  subjects  devoted  to  those  purposes, 
and  prepared  by  means  of  injection,  immersion  in 
spirits  of  wine,  &c. 

The  reader  will  observe,  that,  in  general,  the  mus- 
cles of  one  side  of  the  body  only  are  described,  because 
all  the  muscles  of  the  body  have  correspondent  ones 
on  the  opposite  side,  with  a  few  exceptions,  which 
are  pointed  out. 

The  Bursae  Mucosae  met  with  in  the  dissection  of 
the  muscles  are  not  regularly  enumerated;  but  it  is 
to  be  understood,  that  wherever  tendons  are  des- 
cribed as  rubbing  on  bones,  muscles,  or  other  ten- 
dons, a  sac  is  formed  by  the  surrounding  cellular 
membrane,  secreting  synovia,  to  lubricate  the  parts 
in  motion. 


CHAPTER    I. 
DISSECTION   OF   THE    ABDOMEN. 


SECTION      I . 

Muscles  of  the  abdomen,  and  the  parts  connected  with 
them  in  dissection. 

To  display  these  muscles  which  are  ten  in  number, 
five  on  each  side,  an  incision  should  be  made  through 
the  integuments,  from  the  sternum  to  the  os  pubis; 
this  should  be  crossed  by  another  passing  immedi- 
ately below  the  umbilicus:  dissect  off  the  flaps;  and 
you  will  expose, 

1.  THE  OsLiauus  DESCENDENS  EXTERNUS. — 
This  muscle  is  quite  superficial,  and  covers  the  whole 
of  the  anterior  part  of  the  abdomen.  The  muscular 
part  is  closely  covered  by  a  thin  expansion  of  cel- 
lular substance,  which  should  be  removed  along  with 
the  integuments. 

Origin:  By  eight  angular  fleshy  slips,  from  the 
lower  edges  and  external  surfaces  of  the  eight  in- 
ferior ribs,  at  a  little  distance  from  their  cartilages^ 
the  five  superior  slips  unite  on  the  ribs  by  digitations 
with  the  serratus  major  anticus;  and  the  three  inferior 
are  connected  with  the  attachments  which  the  latis- 
simus  dorsi  has  to  the  ribs.  Often  there  are  only 
seven  portions.  To  gain  a  complete  view  of  this 
muscle,  the  neighboring  portions  of  the  pectoralis 
major,  serratus  anticus,  and  latissimus  dorsi  should  be 
dissected  with  it. 


16  LONDON    DISSECTOR,  OR 

The  muscular  fibres  proceed  obliquely  downwards 
and  forwards,  and  about  tbe  middle  of  the  side  of 
the  belly  terminate  abruptly  in  a  thin  broad  tendon, 
which  is  continued  in  the  same  direction  over  all  the 
forepart  of  the  belly.  Here  it  covers  the  anterior 
surface  of  the  rectus  abdominis;  it  is  very  thin  at  the 
upper  part,  where  the  rectus  lies  on  the  cartilages  of 
the  ribs,  and  is  often  removed  by  the  beginner,  unless 
he  is  very  cautious. 

Insertion:  Tendinous  and  fleshy,  into  two  anterior 
thirds  of  the  outer  edge  of  the  spine  of  the  os  ilium; 
tendinous,  into  the  whole  length  of  Poupart's  liga- 
ment, the  os  pubis,  the  ensiform  cartilage,  and  the  whole 
length  of  the  linea  alba. 

This  muscle  called  also  the  external  oblique,  the 
descending  oblique^  or  the  obliquus  major,  aids  in 
respiration,  in  flexing  the  trunk  forwards,  in  raising 
the  pelvis  obliquely  when  the  ribs  are  fixed;  in  sup- 
porting the  abdominal  viscera,  and  in  the  expulsion  of 
the  urine,  the  faeces,  and  the  foetus. 

In  the  examination  of  this  muscle,  the  following 
points  should  be  observed: 

The  LINEA  ALBA,  a  white  line  running  along  the 
middle  of  the  abdomen,  from  the  cartilage  ensiformis 
to  the  os  pubis;  formed  by  the  tendinous  fibres  of  the 
two  obliqui  and  the  transversalis  muscles,  interlacing 
with  their  fellows  on  the  opposite  side. 

LINEA  SEMILUNARIS,  a  semi-circular  white  line, 
running  from  the  os  pubis  obliquely  upwards  over  the 
side  of  the  abdomen,  at  the  distance  of  about  four 
inches  from  the  linea  alba;  formed  by  the  tendons  of  the 
two  oblique  and  transverse  muscles  uniting  at  the  edge 
of  the  rectus,  before  they  separate  to  form  its  sheath. 

LINE^E  TRANSVERSE  three  or  four  white  lines, 
crossing  from  the  linea  semilunaris  to  the  linea  alba.; 
formed  by  the  tendinous  intersections  of  the  rectj 
shining  through  the  strong  sheath  which  covers  them: 


GUIDE    TO    ANATOMY.  17 

These  are  not  evident  in  all  subjects  in  this  stage  of 
the  dissection. 

UMBILICUS,  or  Navel.  This,  which  before  the  in- 
teguments were  removed,  was  a  depression,  appears 
now  a  prominence;  it  consists  of  condensed  cellular 
membrane: — In  the  foetus,  it  was  a  foramen  which 
gave  passage  to  the  two  umbilical  arteries,  the  um- 
bilical vein,  and  the  urachus. 

ANNULUS  ABDOMINALIS,  or  Ring,  an  oblique  slit 
or  opening  just  above  the  angle  of  the  pubis;  formed 
by  the  tendon  of  the  pxternal  oblique,  divided  into 
two  portions  called  the  pillars  or  columns  of  the  ring, 
one  of  which  (the  superior  or  internal)  is  attached  to 
the  symphysis,  and  the  other  (the  inferior  or  external) 
to  the  angle  of  the  pubis;  and  allowing  a  passage  to 
the  spermatic  cord  in  the  male,  and  the  ligamentum 
teres  of  the  uterus  in  the  female.  This  slit  is  very 
improperly  named  a  ring,  since  its  figure  is  triangular, 
the  pubis  is  the  base,  the  two  columns  are  the  two 
sides  of  the  triangle.  The  apex  has,  indeed,  a 
rounded  figure  in  consequence  of  some  transverse 
fibres,  which  connect  the  two  columns  where  they 
first  separate;  and  it  points  obliquely  upwards  and 
outwards.  It  belongs  to  the  external  oblique  alone, 
there  being  no  such  opening,  either,  in  the  internal 
oblique,  or  the  transversalis;  it  is  much  smaller  in  the 
female  than  in  the  male. 

LIGAMENTUM  INGUINALE,  seu  Poupartii,  seu  Fal- 
lopii,  a  strong  ligament,  stretching  from  the  anterior 
superior  spinous  process  of  the  os  ilium,  to  be  fixed 
to  the  spine  of  the  os  pubis.  This  in  truth  is  merely 
the  lower  edge  of  the  tendon  of  the  obliquus  externus 
abdominis,  although,  in  compliance  with  received  no- 
tions, I  have  described  it  as  a  separate  ligament.  It 
covers  the  femoral  vessels  and  nerves,  and  certain 
muscles,  and  has  lately  been  often  described  under 
the  name  of  the  CRURAL  ARCH.  It  is  also  the  same 
2* 


18  LONDON    DISSECTOR,  OR 

part  as  the  posterior  column  of  the  abdominal  ring-. 
The  student  should  not  be  confused  by  this  multitude 
of  names;  he  should  remember  that  the  crural  arch, 
the  inferior  or  outer  column  of  the  abdominal  ring, 
Poupart's  or  the  inguinal  ligament,  are  so  many  names 
applied  to  the  inferior  border  of  the  tendon  of  the 
external  oblique. 

The  student  should  now  dissect  the  parts  in  the 
groin,  and  examine  the  situation  of  the  great  inguinal 
vessels. 

In  removing  the  skin  from  the  groin,  he  will  not 
find  a  strong  regular  fascia,  as  on  the  outer  part  of 
the  thigh,  but  a  confused  and  irregular  aponeurosis 
coming  off  from  the  abdomen,  and  going  down  upon 
the  thigh;  strengthened  by  the  intermixture  of  con- 
densed cellular  substance,  and  very  loose  above  the 
great  vessels. 

Immediately  under  the  skin,  and  above  this  apo- 
neurosis, you  perceive  a  congeries  of  lymphatic 
glands,  and  sometimes  the  lymphatic  vessels  them- 
selves can  be  distinguished  by  their  semi-transparent 
coats,  and  knotted  appearance.  Also,  immediately 
under  the  skin,  you  will  find  the  VENA  SAPHENA 
running  from  below  upwards,  at  first  lying  on  the 
fascia,  and  then  gradually  sinking  through  it  to  join 
the  femoral  vein,  about  an  inch  below  Poupart's  liga- 
ment. 

On  removing  this  irregular  fascia,  we  come  down 
upon  the  great  vessels,  which  lie  deeply  imbedded  in 
cellular  substance,  and  are  closely  invested  and  sup- 
ported by  a  firm  cellular  sheath,  or  fascia.  This 
should  all  be  cautiously  removed  with  the  scissors, 
together  with  some  lymphatic  glands  imbedded  in  the 
fat.  Observe  the  order  in  which  the  parts  are  situ- 
uated  under  the  crural  arch: — that  the  great  external 
iliac  vein  lies  next  to  the  pubis; — that  the  external 
iliac  artery  is  on  the  outside  of  this,  in  close  con- 


GUIDE    TO    ANATOMY.  19 

tact  with  it; — that  the  anterior  crural  nerve  is  half 
an  inch  exterior  to  the  artery,  and  lies  on  the  iliacus 
internus; — and  that  the  outer  half  of  the  space  left 
under  the  crural  arch  is  filled  by  the  psoas  magnus 
and  iliacus  internus  muscles.  Observe  how  the  cru- 
ral arch  is  stretched  over  the  parts  just  enumerated; 
how  it  forms  a  thin,  but  firm,  sharp,  and  crescent- 
shaped  edge  towards  the  pubis  (constituting  the  seat 
of  stricture  in  the  femoral  hernia,  and  sometimes 
called  Gimbernafs  ligament;) — how  the  artery  is 
placed  in  relation  to  the  angle  of  the  pubis  and  spine 
of  the  ilium,  passing  under  the  middle  of  the  arch. 

The  dissection  of  the  other  abdominal  muscles  may 
now  be  continued. 

Dissect  off  the  serrated  origin  of  the  external  ob- 
lique from  the  ribs,  and  from  the  spine  of  the  os  ilium, 
and  detach  it  from  the  obliquus  internus,  which  lies 
below  it,  and  which  is  connected  to  it  by  loose  cellular 
substance,  and  by  small  vessels.  Continue  to  separate 
the  two  muscles,  till  you  find  their  tendons  firmly  at- 
tached, i.  e.  a  little  way  beyond  the  linea  semilunaris. 
Separate  the  tendon  from  the  crural  arch  to  within 
half  an  inch  of  the  abdominal  ring. 

2.  OBLIQ.UUS  ASCENDENS  INTERNUS. — It  is  covered 
anteriorly  by  the  obliquus  descendens  externus,  and 
posteriorly  by  the  latissimus  dorsi.  In  its  action  it 
assists  the  obliquus  externus;  bending  the  trunk,  how- 
ever, in  the  reverse  direction,  so  that  this  muscle  on 
one  side  co-operates  with  the  obliquus  externus  of  the 
opposite. 

Origin:  By  short  tendinous  fibres,  which  soon 
become  fleshy,  from  the  whole  length  of  the  spine 
of  the  os  ilium,  and  from  the  fascia  lumborum;*  also 
fleshy  from  the  outer  half  of  Poupart's  ligament. 


*  A  tendinous  fascia  common  to  this  and  certain  muscles  of  the  back,, 
as  the  serratus  posticus  inferior. 


The  fibres  run  in  a  radiated  direction;  the  upper 
fibres  ascend  towards  the  sternum;  the  central  pass 
more  transversely  across  the  abdomen;  and  the  infe- 
rior descend  towards  the  pubis.  The  fleshy  belly  of 
this  muscle  extends  beyond  that  of  the  external 
oblique,  before  it  terminates  in  a  flat  tendon. 

Inserted  into  the  cartilages  of  the  six  or  seven 
lower  ribs, — fleshy  into  the  three  inferior,  and,  by  a 
tendinous  expansion,  which  is  extremely  thin,  resem- 
bling1 cellular  membrane,  into  the  four  superior,  and 
also  into  the  ensiform  cartilage.  The  sheet  of  tendon 
in  which  the  fleshy  belly  ends,  is  continued,  single 
and  undivided,  into  the  linea  semilunaris;  there  it 
splits  into  two  parts,  one  passing  in  front  and  the 
other  behind  the  rectus  muscle,  and  finally  unite  in 
the  linea  alba;  but  below  the  umbilicus  the  whole 
tendon  of  the  internal  oblique  passes  along  with  that 
of  the  external  oblique  before"  the  rectus.  The  in- 
ferior edge  of  the  muscle  extends  in  a  nearly  straight 
direction  over  the  spermatic  chord  to  be  fixed  by  a 
tendinous  attachment  to  the  angle  of  the  pubis. 

It  is  sometimes  called  the  obliquus  internus  abdo- 
minis; — the  obliquus  ascendens; — or  obliquus  minor. 

About  the  middle  of  Poupart's  ligament,  a  delicate 
fasciculus  of  fibres  is  sent  off  from  this  muscle  over 
the  spermatic  cord,  as  it  passes  under  its  edge  in  its 
way  to  the  ring.  This  is  named  the 

CREMASTER,  and  is  continued  down  on  the  cord, 
till  it  is  insensibly  lost  on  the  tunica  vaginalis  testis; 
it  will  be  seen  in  the  dissection  of  the  "scrotum:  Its 
use  is  to  suspend,  draw  up,  and  compress  the  testicle. 

We  must  now  dissect  the  attachments  of  the  inter- 
nal oblique,  continuing  our  dissection  from  behind 
forwards,  and  separate  it  from  the  transversalis  ab- 
dominis,  which  lies  beneath  it.  This  separation  may 
be  continued  till  the  tendons  of  the  two  muscles 
become  inseparable.  As  this  muscle  lies  closely 


GUIDE    TO    ANATOMY.  21 

upon  the  transversal  is,  caution  is  required  to  avoid 
detaching  hoth  muscles  together. 

3.  TRANSVERSALIS  ABDOMINIS  lies  beneath  the 
last  muscle,  and  reposes  upon  the  peritoneum.-— 
Jlrises,  tendinous,  from  the  fascia  lumhorum,  and 
back  part  of  the  spine  of  the  os  ilium;  fleshy  from 
all  the  remaining  part  of  the  spine  of  the  ilium,  and 
from  the  inner  surface  of  Poupart's  ligament;  and 
fleshy  from  the  inner  surface  of  the  cartilages  of  the 
seven  lower  ribs,  where  its  fibres  meet  those  of  the 
diaphragm. 

The  fleshy  fibres  proceed  transversely,  and  end  in 
a  flat  sheet  of  tendon,  which  passes  with  the  pos- 
terior layer  of  the  internal  oblique  behind  the  rectus, 
and  is  inserted  into  the  ensiform  cartilage,  and  into 
the  whole  length  of  the  linea  alba;  midway,  however, 
between  the  umbilicus  and  os  pubis,  a  slit  or  fissure 
is  formed  in  this  tendon,  through  which  the  rectus 
abdominis  passes;  and  the  remainder  of  the  tendon 
passes  before  the  rectus,  to  be  inserted  into  the  lower 
part  of  the  linea  alba,  and  the  os  pubis. 

Where  the  transversalis  is  detached  from  its  ori- 
gins, and  turned  back  towards  the  linea  semilunaris, 
the  peritoneum  is  laid  bare,  except  in  the  neighbor- 
hood of  the  crural  arch,  where  it  is  covered  by  a 
thin  fascia  arising  from  Poupart's  ligament,  and  con- 
tinued upwards  between  the  peritoneum  and  transver- 
salis muscle,  until  it  is  gradually  lost.  This  is  named 
by  Mr.  Cooper,  its  discoverer,  the  fascia  transversalis; 
it  prevents  the  bowels  from  being  protruded  under  the 
inferior  margins  of  the  obliquus  internus  and  trans- 
versalis muscles.  It  i§  perforated  about  the  middle 
between  the  ilium  and  pubes,  by  an  opening  for  the 
passage  of  the  spermatic  chord,  which  then  goes 
obliquely  downwards,  inwards,  and  forwards  to  the 
ring  of  the  external  oblique.  Thus  the  abdominal 
ring  is  a  canal,  having  an  upper  or  internal  opening, 


22  LONDON    DISSECTOR,  OR 

formed  in  the  fascia  transversalis,  and  a  lower  or 
external  one  in  the  tendon  of  the  obliquus  externus. 
The  next  muscle  to  be  described  is  the 

4.  RECTUS  ABDOMINIS. — Jlrises,  by  a  flat  tendon, 
from  the  forepart  of  the  os  pubis;  as  it  ascends,  its 
fleshy  belly  becomes  broader  and  thinner. 

Inserted,  by  a  thin  fleshy  expansion,  into  the  ensi- 
form  cartilage,  and  the  cartilages  of  the  three  inferior 
true  ribs. 

Situation:  This  pair  of  muscles  is  situated  on  each 
side  of  the  linea  alba,  enclosed  in  a  sheath  formed  by 
the  tendons  of  the  oblique  and  transversalis  muscles. 
Thus  the  rectus  has  in  front  of  it  the  whole  tendon 
of  the  external  oblique,  and  half  of  the  internal;  and 
behind  it,  the  remaining  half  of  the  tendon  of 
the  internal  oblique  and  the  entire  tendon  of  the 
transversalis.  The  muscle  is  generally  divided  by 
three  tendinous  intersections;  the  first  at  the  umbili- 
cus, the  second  where  it  runs  over  the  cartilage  of 
the  seventh  rib,  and  the  third  between  these;  and 
there  is  commonly  a  half  intersection  below  the  um- 
bilicus. These  intersections  constitute  the,  LINE  JE 

TRANSVERSE. 

At  the  os  pubis,  on  each  side  of  the  linea  alba,  and 
inclosed  in  the  lower  part  of  the  sheath  of  the  rectus, 
is  sometimes  found  a  small  muscle,  named 

5.  PYRAMIDALIS. — Origin:  Tendinous  and  fleshy, 
of  the  breadth  of  an  inch  from  the  os  pubis,  anterior 
to  the  origin  of  the  rectus. 

Insertion:  By  an  acute  termination,  near  half-way 
between  the  os  pubis  and  umbilicus,  into  the  linea 
alba  and  inner  edge  of  the  rectus  muscle. 


GUIDE   TO    ANATOMY.  23 


SECTION     II. 

Anatomy  of  Hernia.* 

It  is  of  considerable  importance  in  this  dissection 
to  have  a  good  body.  That  of  a  strong  muscular 
man  is  not  so  well  adapted  for  the  display  of  the 
anatomy  of  the  groin,  as  that  of  a  person  who  has 
died  of  a  lingering  disease.  The  body  of  a  male  is 
the  best  for  the  dissection  of  the  inguinal  canal,  and 
that  of  a  female  for  the  parts  connected  with  femoral 
hernia.  The  subject  is  to  be  so  placed  that  the  ab- 
dominal muscles  may  be  made  tense:  this  is  most 
conveniently  done  by  placing  a  block  of  wood  under 
the  loins.  To  put  the  fasciae  of  the  thigh  upon  the 
stretch,  one  leg  ought  to  hang  over  the  side  of  the 
table.  The  dissection  of  the  upper  part  of  the 'exter- 
nal oblique  is  to  be  made  according  to  the  general 
rule  of  removing  all  the  cellular  membrane  from  the 
muscular  fibre;  but  this  plan  must;  not  be  followed 
lower  down  than  to  a  line  drawn  from  the  one  ante- 
rior superior  spinous  process  of  the  ilium  to  the  other; 
here,  the  skin  only  should  be  raised;  it  may  be  carried 
down  to  three  fingers'  breadth  below  the  line  of 
Poupart's  ligament.f  By  this  method  we  shall  leave 
upon  the  groin  a  quantity  of  condensed  cellular  mem- 
brane, between  the  layers  of  which  is  the  arteria 
epigastrica  superficialis;  this  membrane  may  be  traced 
from  that  which  covers  the  pectoralis  muscle  and  the 
upper  part  of  the  muscles  of  the  abdomen;  it  has 
generally  received  the  name  of  fascia  superficialis 
communis,  because  it  is  of  equal  importance  to  the 

*  Shaw's  Manual. 

f  Tendon  of  the  external  oblique;  Fallopian  or  Poupart's  ligament; 
crural  arch;  ligament  of  the  thigh;  femoral  ligament. 


24  LONDON    DISSECTOR,  OR 

inguinal  and  femoral  hernia.  This  fascia*  is  now  to 
be  dissected  from  the  tendon  of  the  external  ohlique. 
It  has  a  very  slight  attachment  to  the  expanded  tendon, 
and  the  union  between  it  and  the  spermatic  cord  is  so 
slight,  that  the  handle  of  the  knife  can  be  pushed 
between  them  as  far  down  as  to  the  bottom  of  the 
scrotum.  The  attachment  between  the  iliacf  portion 
of  Poupart's  ligament  and  this  fascia  is  very  strong; 
but  the  connection  between  the  pubic  portion  of  the 
ligament  and  the  fascia  is  so  slight,  that  the  handle  of 
the  knife  is  sufficient  to  destroy  it.  We  can  separate 
the  fascia  with  great  ease  for  about  an  inch  below 
the  edge  of  this  part  of  the  ligament,  but  we  cannot 
lift  it  farther  without  using  the  knife;  for  the  fascia 
becomes  intimately  united  to  the  inguinal  glands  and 
to  the  fascia  lata.  Although  we  have  raised  this 
fascia,  the  accurately  defined  pillars  of  the  abdominal 
ring,  which  are  generally  represented  in  plates  as  the 
first  stage  of  the  dissection,  will  not  yet  be  visible; 
but  farther  dissection  will  be  required,  to  show  them; 
for  a  fascia,  which  shall  be  presently  described,  covers 
the  ring,  so  that  only  a  prominence  is  seen,  and  which 
we  shall  find  to  be  formed  by  the  spermatic  cord. 

It  is  of  great  importance  to  make  this  dissection  in 
the  manner  that  has  been  pointed  out,  because  much 
of  the  pathology  of  femoral  hernia  may  be  explained 
by  it  By  looking  narrowly  into  the  depression 
which  has  been  formed  by  raising  the  fascia  superfi- 
cialis,  we  may  see  lymphatic  vessels  passing  across 
from  the  glands  to  perforate  a  membrane,  which, 

*Fascia  superficial  of  Mr.  Cooper;  described  by  Camper  and  many 
others  as  only  a  membranous  layer;  by  Scarpa,  as  a  prolongation  of  the 
fascia  lata.  In  the  scrotum  of  the  fetus  it  forms  the  external  lamina  of 
the  peritoneum  of  Langenbeck. 

fThe  terms  iliac  and  piibic  are  better  than  external  and  internal. 
The  length  of  the  Poupart  ligament  may  be  divided  into  three  portions: 
two  of  the  thirds  are  called'tZwc,  the  other  pubic,  being  that  which  is 
nearest  to  the  pubes. 


GUIDE    TO    ANATOMY.  25 

though  it  appears  to  be  a  continuation  of  the  lower 
edge  of  Poupart  's  ligament,  has  been,  by  some,  de- 
scribed as  a  distinct  fascia,  under  the  name  of  cribri- 
form, in  consequence  of  the  appearance  which  it  pre- 
sents when  the  lymphatics  are  cut  short.  Occasionally 
a  small  gland  is  projected  through  the  membrane. 
The  general  course  of  the  femoral  hernia  is  either  to 
displace  this  gland,  or  to  break  through  the  meshes  of 
the  net- work;  and  then  it  will  pass  into  the  hollow 
which  we  have  just  described.  The  natural  course  of 
the  hernia  would  be,  to  descend  upon  the  thigh;  but 
it  is  prevented  from  passing  farther  down,  than  about 
an  inch,  on  account  of  the  close  connection  which 
exists  between  the  fascia  superficialis  and  the  glands 
of  the  groin;  but  when  the  hernia  increases  in  size, 
as  it  is  prevented  from  descending  upon  the  thigh,  it 
turns  up  and  breaks  through  the  slight  connection 
which  there  is  between  the  pubic  part  of  the  liga- 
ment and  the  fascia  superficialis,  and  thus  takes  the 
place  of  an  inguinal  hernia.  This  explains  to  us  that 
the  acute  angle  made  in  the  gut  is  the  principal  cause 
of  stricture  in  femoral  hernia;  and  from  the  knowledge 
of  this,  we  deduce  principles  upon  which  we  must 
proceed  to  attempt  the  reduction  of  femoral  hernia, 
when  so  situated.  We  must  endeavour  to  bring  the 
base  of  the  sac  to  a  straight  line  with  the  neck;  and 
to  succeed  in  doing  this,  we  must  first  push  the  tumor 
downwards. 

It  has  occasionally  happened  that  a  femoral  hernia 
has  passed  up  before  the  surgeon  had  finished  the 
operation.  We  have  heard  the  surgeon  blamed  for 
operating  in  such  a  case.  It  has  been  said,  that  the 
gut  going  up  before  the  stricture  was  cut,  proved  that 
there  was  no  necessity  for  the  operation;  but  instead 
of  joining  in  the  censure,  we  think  that  it  would  be 
even  advisable,  in  some  cases,  to  cut  through  the 
fascia  superficialis,  so  as  to  allow  the  sac  to  come  to 
3 


26  LONDON    DISSECTOR,  OR 

a  straight  line,  rather  than  to  persevere  long  in  the 
use  of  the  taxis.  All  who  have  seen  many  cases  of 
femoral  hernia  must  allow,  that  a  cut  through  the  skin 
and  fascia,  in  an  early  stage,  in  many  cases,  would 
not  be  so  dangerous  as  a  protracted  attempt  to  reduce 
the  gut  hy  the  taxis.  We  have  further  to  consider, 
that  if  it  be  not  possible  to  reduce  a  hernia,  after 
having  cut  through  the  fascia  superficialis,  that  it 
never  would  have  been  reduced  by  the  taxis;  in  that 
case  all  the  steps  of  the  operation  must  be  performed. 
We  now  return  to  the  anatomy  of  the  inguinal 
hernia.  If  we  pull  the  spermatic  cord  towards  the 
scrotum,  we  shall  see  a  thin  fascia  passing  off  from 
the  tendon  of  the  external  oblique  and  attached  to  the 
cord.  It  has  been  called  fascia  propria.  It  is  very 
strong  in  cases  of  old  hernia;  but  even  in  the  natural 
state  of  the  parts,  it  is  so  distinct  that  it  obscures  the 
margins  of  the  ring,  (a)  By  cutting  this  thin  fascia 
where  it  is  connected  with  the  cord,  and  by  letting  go 
the  cord,  the  upper  part  of  the  pillars  of  the  ring  will 
be  distinctly  shown;  but  to  make  the  opening  of  the 
ring  quite  apparent,  we  must  remove  the  loose  fat 
with  the  forceps  and  scissors  from  the  lower  part  of 
the  cord;  we  shall  then  have  such  a  view  as  is  given 
in  plates  as  the  first  stage  of  the  dissection.  This 
opening  has  been  called  a  ring.*  but  it  might  with 
more  reason  be  described  as  a  triangle,  the  base  of 
which  is  the  os  pubis,  and  the  apex  the  splitting  of  the 

(a)  While  the  fascia  superficialis  was  overlooked;  Camper  described 
a  covering  to  the  cremaster  muscle,  extended  from  the  edges,  of  the 
external  abdominal  ring.  This,  however,  has  since  been  traced  in  con- 
tinuation with  the  fascia  superficialis;  is  a  part  of  that  fascia;  and  covers 
the  cremaster  as  the  extended  aponeurosis  does  the  other  superficial 
muscles  of  the  body.  I  would  rather  retain  the  name  of  Camper's  fascia, 
to  this  slip  of  the  superficial  fascia;  then  call  it  fascia  propria;  lest  it 
might  be  confounded  with  the  fascia  propria  of  a  femoral  hernia,  that  is 
derived  from  the  cribriform  portion  of  the  crural  sheath. 

*  Inguinal  ring;  ring  of  the  external  oblique;  or  external  abdominal 
ring.  The  anatomy  of  the  canal  is  most  accurately  described  in  the 
folio  edition  of  Mr. 'Charles  Bell's  Dissections,  published  in  1799. 


GUIDE    TO    ANATOMY.  27 

tendinous  fibres  of  the  external  oblique,  and  which  is 
rounded  off  by  a  set  of  cross  fibres.  The  superior 
side,  or  pillar,  is  simply  inserted  into  the  symphysis 
pubis;  but  in  the  attachment  and  form  of  the  lower 
pillar  there  is  a  provision  to  prevent  the  compression 
of  the  spermatic  cord  during  the  contraction  of  the 
muscles,  and  it  is  thus — the  inferior  pillar  is  formed 
by  the  pubic  extremity  of  Poupart's  ligament,  which 
is  not  a  rounded  tendon  that,  viewing  it  on  the  out- 
side, we  sh6uld  expect  it  to  be,  but  it  is  so  formed, 
that  part  of  it  passes  onwards  to  be  attached  to  the 
linea  ileopectinea  by  a  flat  broad  horizontal  tendon, 
while  its  more  external  part  is  inserted  into  the  tuber- 
cle of  the  pubes;  so  that  by  this  form  of  insertion 
there  is  a  groove  made  for  the  lodgment  of  the  sper- 
matic cord. 

The  tendon  of  the  external  oblique  is  now  to  .be 
cut  through  in  two  directions;  one  in  a  line  drawn 
from  the  superior  anterior  spinous  process  of  the  ilium 
to  the  linea  alba,  and  the  other  in  the  linea  alba  to  the 
pubes.  The  tendon  of  the  external  oblique  is  to  be 
carefully  separated  from  the  internal  oblique,  and  is 
to  be  fastened  by  a  hook  to  the  fore  part  of  the  thigh. 
This  will  give  us  a  view  of  a  great  part  of  the  ingui- 
nal canal.  The  cord  will  be  seen  lying  under  the 
lower  margin  of  the  internal  oblique,  and  so  connect- 
ed by  cellular  membrane  to  the  edge  of  the  muscle, 
that  it  is  difficult  for  a  student  in  his  first  dissection 
to  tell  what  is  muscle  and  what  is  cord.  This  is  in  a 
great  measure  owing  to  the  cremaster  muscle,  for  it 
certainly  varies  considerably  in  the  manner  in  which 
it  takes  its  origin;  the  view  may  be  made  more  dis- 
tinct by  pulling  the  cord  in  a  direction  towards  the 
scrotum,  and  taking  off  the  cellular  membrane  from 
it  and  from  the  margin  of  the  internal  oblique.  By 
doing  so,  we  shall  see  that  the  internal  oblique  is  not 
attached  to  the  whole  extent  of  Poupart's  ligament,  but 


28  LONDON    DISSECTOR,  OR 

that,  at  two  inches  and  a  half  from  the  symphysis  pubis, 
its  attachment  to  the  ligament  ceases;  it  then  passes 
in  the  form  of  an  arch,  to  the  tubercle,*  and  to  the 
linea  ileo-pectineaf  of  the  os  pubis,  so  as  to  assist  in 
closing  the  space  behind  the  external  ring.  At  the 
termination  of  the  connection  of  the  internal  oblique 
to  Poupart's  ligament,  the  fibres  which  form  the  cre- 
master  muscle  come  off;  but  as  these  fibres  occasion- 
ally arise  from  Poupart's  ligament,  the  cord  some- 
times appears  to  perforate  the  internal  obliqueij  but 
in  the  greater  number  of  cases,  it  is  sufficiently  clear 
that  the  cord  passes  under  the  internal  oblique,  not 
through  it.  In  this  part  of  the  dissection  we  may 
observe  a  nerve  running  through  the  internal  oblique  to 
pass  on  the  cord,— it  is  the  spermaticus  superficial. 
The  next  stage  of  the  dissection  is  to  show  the  rela- 
tion of  the  transversalis  to  the  cord.  It  will  be  very 
difficult  to  raise  the  internal  oblique  from  the  trans- 
versalis, if  we  commence  the  separation  at  the  lower 
edge  of  the  muscle;  but  by  cutting  through  those 
fibres  of  the  internal  oblique,  which  are  connected 
with  the  superior  anterior  spinous  process  of  the  ilium, 
we  shall  find  some  cellular  membrane,  and  a  branch 
of  the  artery  called  circumflexa  ilii,  lying  upon  the 
transversalis  muscle,  which  will  mark  the  line  in 
which  we  are  to  dissect,  so  as  to  raise  the  internal 


*  Spine  of  the  os  pubis;  tuberculum  spinosum;  tuberdsity  of  the  pubes. 

t  Linea  ileo-pectinea;  linea  iniiominata,  continuous  with  the  crista. 

$  M.  Cloquet  describes  the  cremaster  as  formed  by  some  fibres  of  the 
obliquus  internus,  which  are  pulled  down  by  the  testicle  and  guberna- 
ciilum,  during  the  descent.  He  says  that  these  fibres  have  two  distinct 
attachments,  one  to  the  belly  of  the  obliquus  internus,  and  the  other  to 
the  os  pubis;  so  that  each  fibre  forms  a  loop  (des  anses,)  similar  to 
extensible  cords,  which,  when  fixed  at  their  two  extremities,  are 
drawn  down  in  the  middle.  He  also  says  that  the  testicle  occasionally 
passes  through  the  substance  of  the  internal  oblique,  and  theu,  the  same 
appearance  of  fibres  is  found  both  before  and  behind  the  testicle;  and 
that  an  inguinal  hernia  in  a  female  frequently  pushes  down  some  of  the 
fibres  of  the  internal  oblique  before  it,  so  as  to  form  "tin  muscle  cremas- 
ter accidentel." 


GUIDE    TO    ANATOMY.  29 

oblique  from  the  transversalis.  The  internal  oblique 
is  to  be  separated  from  the  transversalis,  and  from  its 
connection  with  Poupart's  ligament,  as  far  as  the 
origin  of  the  cremaster,  and  it  is  then  to  be  turned 
over  towards  the  linea  alba.  The  whole  of  the  mar- 
gin of  the  transversalis  will  now  be  seen,  and  we  may 
observe  that  its  relation  to  the  cord  is  very  nearly  the 
same  as  that  of  the  internal  oblique;  indeed,  the 
tendons  of  the  two  muscles  are  so  closely  connected 
with  each  other,  that  it  is  almost  impossible  to  sepa- 
rate them.  It  will  be  also  apparent  that  the  united 
tendons  of  these  muscles,  by  their  insertion  into  the 
linea  ileo-pectinea,  form  the  grand  protection  against 
hernia  taking  place  through  the  exte/nal  abdominal 
ring;  but  when  this  part  is  weak,  in  consequence  of 
the  deficiency  of  the  tendons,  that  hernia  which  is 
called  direct,  or  ventro  inguinal,  may  take  place. 
The  muscular  fibres  of  the^transversalis  are  now  to 
be  very  carefully  detached  from  Poupart's  ligament, 
and  then  they  are  to  be  scraped,  not  cut,  from  the 
layer  of  condensed  cellular  membrane,  which  is  called 
the  fascia  transversalis.* 

We  have  seen  the  cord  pass  through  the  external 
oblique,  and  under  the  margins  of  the  internal  oblique 
and  transversalis, — and  we  should  now  see  the  inter- 
nal ring,  described  by  Mr.  Cooper;  but  this  ring  must 
be  made.  When  we  pull  the  cord  towards  the  groin, 
we  see  part  of  the  cellular  membrane  which  lies  under 
the  transversalis  muscle  passing  down  upon  it  in  a 
conical  form.  If  we  cut  this  membrane  from  the 
•cord,  and  push  it  up,  and  then  let  the  cord  go,  there 
will  be  a  hole,  formed  in  the  shape  of  a  ring,  but 
which,  on  its  iliac  side  only,  has  a  distinct  margin,  for 
on  its  pubic  side  there  is  only  the  cellular  membrane 

*  Fascia  transversalis,  of  Mr.  Cooper;  fascia  longitudinalis,  or  reflexa, 
of  M.  Cloqui't;  condensed  cellular  membrane  between  the  peritoneum 
and  transversalis  muscle,  of  many  authors. 

3* 


30  LONDON    DISSECTOR,  OR 

surrounding  the  epigastric  artery  and  veins.  We 
may  observe  also,  that  the  cord  at  this  point  has  lost 
its  rounded  form — that  the  vessels  are  not  bound 
together,  as  they  are  at  the  external  ring,  but  that  the 
component  parts,  separating  from  each  other,  give 
the  cord  a  flattened  form.  Having  now  made  an 
internal  ring,(a)  we  should  attend  to  the  situation  of 
the  epigastric  artery.  It  generally  arises  from  the 
pubic  side  of  the  external  iliac  artery,  just  before  it 
passes  under  Poupart's  ligament.  It  will  be  found  to 
descend  a  little,  and  then  to  proceed  upwards  towards 
the  rectus,  passing  upon  the  pubic  edge  of  the  sper- 
matic cord,  and  between  the  fascia  transversalis  and 
the  peritoneum;  it  then  enters  the  substance  of  the 
rectus,  about  midway  between  the  pubes  and  umbili- 
cus. As  this  artery  is  always  on  the  pubic  side  of 
the  spermatic  cord,  it  follows,  that  when  the  inguinal 
hernia  passes  along  the  spermatic  passage,  (which  it 
does  in  nine  out  of  ten  cases,)  the  epigastric  artery 
will  be  on  the  pubic  side  of  the  hernia;  but  in  the 
direct  or  ventro  inguinal  hernia,  the  artery  will  be  on 
the  iliac  side. 

Let  us  now  trace  the  course  of  a  common  hernia  to 
the  scrotum,  and  show  what  coverings  it  may  have, 
and  what  are  the  probable  causes  of  stricture. 

The  muscles  and  the  peritoneum  may  be  cut 
through  in  the  usual  way  of  exposing  the  viscera,  and 
the  flap  held  out  so  that  the  inside  of  the  peritoneum, 
and  the  depression  which  is  found  at  the  part  where 
the  cord  passes  into  the  canal,  may  be  seen.  In  the 
greater  proportion  of  cases,  it  is  .at  this  point  that 
hernia  takes  place.  Having  laid  down  the  transver- 
salis and  internal  oblique  again  in  their  natural  situa- 

(a)  This  opening  is  not  the  creature  of  the  knife,  but  exists  before 
dissection  has  commenced,  as  perfectly  as  that  on  the  upper  part  of  the 
cone  of  a  funnel,  by  which  the  pipe  is  connected  with  the  body  of  the 
article. 


GUIDE    TO    ANATOMY.  31 

tions,  if  we  push  the  finger  from  within  downwards 
into  the  depression  of  the  peritoneum,  we  shall 
exhibit  in  appearance  the  first  stage  of  the  descent  of 
a  hernia.  The  finger  is  as  the  sac  would  be,  above 
the  cord,  and  on  the  iliac  side  of  the  epigastric 
artery:  by  pressing  forward  the  finger,  and  through 
the  peritoneum,  it  will  appear  under  the  margins  of 
the  transversalis  and  internal  oblique;  and  if  pushed 
farther,  it  will  pass  through  the  external  ring.  A 
hernia  lying  at  this  point,  would  be  called  inguinal 
hernia;  but  if  it  were  to  descend  as  far  as  into  the 
scrotum,  it  would  be  called  scrotal  hernia.  This  is 
the  common  course  of  an  inguinal  hernia,  but  its  rela- 
tion to  the  cord  occasionally  varies.  When  we  look 
to  the  flattened  and  dispersed  state  of  the  cord  at  its 
upper  part,  we  can  understand  how  it  may  be  split  by 
the  descent  of  a  herniary  tumor.  In  such  a  case,  the 
vas  deferens  is  sometimes  found  on  the  anterior  part, 
and  the  vessels  behind;  but  the  vessels  are  more 
frequently  on  the  fore  part  of  the  sac. 

We  may  now  show  what  coverings  the  sac  of  a 
hernia  would  receive  in  its  passage  to  the  scrotum. 

In  the  common  inguinal  hernia,  the  peritoneum 
pushes  before  it,  that  cellular  membrane  which  has 
been  called  part  of  the  transversalis  fascia,  and  which 
we  showed  must  be  separated  from  the  cord  before 
the  internal  ring  can  be  made;  this,  when  condensed, 
forms  the  innermost  covering  of  the  sac.  The  hernia 
then  passes  under  the  transversalis  and  internal 
oblique,  and  as  the  cremaster  muscle  runs  from  the 
internal  oblique  to  the  cord,  it  follows,  that  if  the 
hernia  lies  above  the  cord,  the  sac  must  be  between 
the  cremaster  and  the  cord;  the  fibres  of  the  cremas- 
ter which  lie  above  the  sac  will  then  be  separated,  by 
it,  from  each  other,  so  that  the  cellular  membrane 
which  connects  the  scattered  fibres,  will  form  that 
which  is  ^called  the  cremastic  or  spermatic  fascia. 


32  LONDON    DISSECTOR,  OR 

The  hernia  then  passes  through  the  external  ring.  In 
the  early  part  of  the  dissection,  there  was  a  mem- 
brane shown  passing  from  the  margins  of  the  ring  to 
the  cord,  so  as  to  make  the  ring  indistinct;  this  mem- 
brane, which  is  sometimes  called  fascia  propria,  must 
also  form  one  of  the  coverings.  The  hernia  may 
now  either  lie  in  the  groin,  or  pass  into  the  scrotum, 
and  in  either  case  it  will  be  covered  by  the  condensed 
cellular  membrane,  called  fascia  superficialis. 

If  a  patient  had  worn  a  truss  for  some  time,  all 
these  fasciae  might  be  distinctly  seen  in  an  operation; 
but  it  is  of  more  importance  to  recollect,  that  the 
peritoneum,  which  forms  the  sac,  and  which,  in  its 
natural  state,  is  very  thin,  would  be  found  very  much 
thickened,  and  particularly  at  the  neck  of  the  sac; 
indeed  it  is  occasionally  so  much  thickened,  that  it 
may  be  separated  into  a  dozen  layers.  But  if  it  were 
necessary  to  perform  an  operation  for  a  hernia  which 
had  come  down  only  a  few  hours  before, — after 
having  cut  through  the  skin  and  fat,  instead  of  finding 
distinct  fascias,  such  as  have  been  described,  only  a 
little  cellular  membrane  would  be  seen  covering  the 
sac,  and  the  sac  itself  would  be  so  thin  and  transpa- 
rent, that  the  color  of  the  gut  may  be  seen  shining 
through  it. 

The  anatomy  of  the  fascia?  in  congenital  hernia  is 
much  the  same;  but  the  sac  which  is  formed  by  the 
tunica  vaginalis,  is  generally  thin  at  the  lower  part, 
but  very  strong  at  the  neck. 

Before  describing  what  are  the  probable  causes  of 
stricture,  there  are  some  circumstances  to  be  recol- 
lected. To  produce  strangulation,  the  gut  must  be 
compressed  in  the  whole  circle;  strangulation  cannot 
be  produced  by  the  muscular  fibres  which  stretch 
over  the  gut,  for  they  relax  occasionally;  as,  for 
example,  when  a  patient  faints.  The  hole  through 
which  the  gut  is  pushed  is  passive;  its  diameter  is 


GUIDE    TO    ANATOMY.  33 

never  diminished,  but  the  protruded  gut  swells,  and  is 
increased  in  size. 

The  most  common  seat  of  stricture  in  inguinal 
hernia  is  the  external  ring;  for  though  we  do  not  see 
the  ring  until  we  have  dissected  the  parts,  still  we  can 
feel  it,  even  before  the  skin  is  removed,  by  pushing 
the  finger  up  along  the  cord.  If  the  sac  has  been 
opened,  if  the  external  ring  has  been  cut,  and  the 
stricture  still  continues,  what  is  the  cause  of  stricture? 
It  cannot  be  produced  by  the  margins  of  the  internal 
oblique  or  transversalis  muscles,  for  they  wjll  relax. 
Since  we  are  told  by  high  authority,  that  the  stricture, 
in  such  a  case,  is  caused  by  the  internal  ring,  we 
cannot  deny  that  it  may  occasionally  happen;  but  we 
should  be  more  inclined  to  say,  that  the  stricture  is 
not  caused  by 'the  internal  ring  itself,  but  by  the  neck 
of  the  sac,  which  is  situated  at  that  part.  Our  reasons 
for  supposing  so,  are  the  following: — In  the  dissection 
of  the  parts,  in  their  natural  or  ruptured  state,  there 
is  no  internal  ring,  until  it  is  made  by  pushing  up  the 
cellular  membrane  which  surrounds  the  cord;  and 
even  then,  if  we  try  its  strength,  we  find  it  very  weak, 
and  particularly  on  the  inner  part;  while  the  neck  of 
the  sac  is  generally  so  strong,  that  we  might  as  easily 
break  a  circle  of  whip  cord  as  tear  it.  The  external 
ring,  and  the  neck  of  the  sac,  may  be  considered  as 
the  most  common  seats  of  stricture;  but  there  are  va- 
rieties, into  the  consideration  of  which  it  would  be 
impossible  to  enter  at  present. 

There  is  a  species  of  inguinal  hernia  called  the 
direct  or  ventro  inguinal,  which  has  been  already  men- 
tioned as  having  the  epigastric  artery  on  its  pubic 
side;  (a)  in  several  other  respects  it  differs  from  the 
common  inguinal  hernia.  It  does  not  come  along  the 
inguinal  canal,  but  passes  directly  through  the  exter- 

(a)  Certainly  the  iliac  side! 


34  LONDON    DISSECTOR,  OR 

nal  ring;  it  is  not  covered  by  the  cremaster  or  any 
part  of  the  fascia  transversalis,  but  only  by  the  fascia 
propria  and  superficialis.(a)  The  peritoneum  is  as 
liable  to  be  thickened  in  this  species  as  in  the  other. 
We  have  seen  in  operation  the  sac  a  quarter  of  an 
inch  in  thickness.  This  kind  of  hernia  does  not  take 
place  often,  but,  in  proportion  to  our  limited  oppor- 
tunities, it  has  occurred  to  us  more  frequently  than  it 
appears  to  have  done  to  Mr.  Cooper. 

The  dissection  of  the  parts  connected  with  femoral 
hernia  may  now  be  made.  We  have  already  de- 
scribed the  first  steps  of  the  dissection.  It  is  abso- 
lutely necessary  that  the  limbs  be  kept  forcibly 
separated  from  each  other,  and  that  the  handle  of  the 
knife  only,  should  be  used  in  removing  the  glands,  as 
we  are  very  apt  to  destroy  some  of  the  'connections  of 
the  fasciae,  if  we  use  a  sharp  knife  while  the  limbs 
are  lying  straight.  When  the  glands  are  removed, 
we  may  see  the  manner  in  which  the  fascia  lata  is 
connected  to  the  Poupart  ligament;  how  it  dips  down 
towards  the  femoral  vessels,  and  how  it  mounts  up 
again  to  cover  the  pectinalis  muscle.  The  part  of 
the  fascia  lata  which  dips  down  towards  the  femoral 
vessels,  will  have  a  crescentic  form;  but  this  will  not 
be  so  distinct  as  is  represented  in  many  plates,  parti- 
cularly in  those  of  Mr.  Hey,  unless  we  cut  through 
the  connection  which  there  is  between  the  fascia  lata 
and  the  sheath  of  the  vessels;  but  by  doing  so,  we 
would  destroy  the  natural  view.  This  part  generally 
receives  the  name  of  superficial  crescentic  arch;*  for 

(a)  By  Ihig  expression,  the  student  would  be  led  to  expect  that  a 
scrotal  hernia  had  two  coverings  from  fasciae  above  the  cremaster; 
while  Camper's  fascia  is  the  only  one  lying  between  that  muscle  and 
the  common  integuments. 

*  Femoral  ligament,  of  Mr.  Hey;  falciform  process  of  the  fascia  lata, 
of  Mr.  Allan  Burns.  All  these  parts  are  accurately  described  in  the 
folio  edition  of  Mr.  Charles  Bell's  Dissections,  published  in  1799.  He 
did  not  give  them  names. 


GUIDE   TO    ANATOMY.  35 

we  shall  afterwards  see  a  deep  one.  It  is  in  this  stage 
of  the  dissection  that  we  can  understand  how  some 
surgeons  have  described  the  femoral  hernia  as  situated 
under  the  fascia  lata,  while  others  have  described  it 
as  lying  above  the  same  fascia;  in  truth,  the  femoral 
hernia  is  above  one  portion  of  the  fascia  lata,  and 
below  another,  for  it  is  under  this  part  which  is  called 
crescentic  arch,  and  above  the  portion  which  covers 
the  pectineal  muscle. 

If  we  pull  away  the  lymphatics  which  are  passing 
from  the  inguinal  glands  to  those  of  the  pelvis,  we 
shall  see  a  number  of  holes  in  a  membrane  which 
connects  the  lower  edge  of  the  Poupart  ligament  to 
the  pectineal  portion  of  the  fascia  lata:  this  part  we 
have  already  noticed.  Though  it  will  not  appear  as 
a  distinct  fascia  in  our  dissection,  still  it  has  received 
the  name  of  fascia  cribriformis  from  Mr.  Cooper;  and 
as  an  addition  to  our  stock  of  names,  we  have,  from 
M.  Cloquet,  septum  crurale.  It  must  be  very  care- 
fully examined,  for  it  is  the  only  weak  part  of  the 
boundary  between  the  pelvis  and  the  thigh;  for,  on 
the  iliac  side  of  this  fascia  cribriformis,  Poupart's 
ligament  is  firmly  attached  to  the  fascia  lata,  and  on 
its  pubic  side  there  is  a  firm  union  between  the  edge 
of  the  third  insertion  of  the  Poupart  ligament  and  the 
portion  of  fascia  lata  which  covers  the  pectinalis 
muscle.* 

We  now  proceed  to  the  examination  of  the  internal 
view.  The  flap  of  the  abdominal  muscles  is  to  be 
held  up,  and  the  peritoneum  is  to  be  carefully  torn 
from  it;  by  which  a  useful  view  will  be  given,  without 
our  using  the  knife  at  all.  At  about  an  inch  from  the 
pubes,  we  see  a  depression,  bounded  by  the  cribriform 
fascia,  through  which  the  lymphatics  pass  into  the 

*  While  at  this  stage  of  the  dissection  the  leg  should  be  moved  in 
different  directions,  to  show  the  effect  of  the  various  positions  in  relax- 
ing or  tightening  the  fasciae. 


36  LONDON    DISSECTOR,  OR 

pelvis  from  the  thigh.  The  part  of  Poupart's  liga- 
ment which  is  on  the  iliac  side  of  this  cavity,  is  very 
firmly  connected  with  the  fascia  which  covers  the 
iliacus  internus  muscle;  and  on  its  pubic  side,  the 
united  tendons  of  the  internal  oblique  and  transversal  is 
muscles  are  inserted  into  the  linea  ileo-pectinea.  If 
we  push  our  finger  into  this  depression,  and  force  it 
through  the  cribriform  fascia,  it  will  pass  down  into 
that  hollow  on  the  fore  part  of  the  thigh,  which  has 
been  already  described  as  the  situation  in  which  a 
femoral  hernia  lies.  The  firm  connection  which 
there  was  between  the  fascia  superficial  is  and  the 
glands  of  the  groin,  would  have  prevented  us  from 
passing  the  finger  farther  down;  but  if  we  turn  up  the 
finger  as  a  hernia  does,  when  it  increases  in  size,  we 
shall  find  that  it  not  only  presses  against  the  superficial 
arch,  but  that  there  is  also  a  resistance  to  it,  caused 
by  a  part  more  deeply  situated;  this  will  afterwards 
be  found  to  have  been  produced  by  that  which  is 
called  the  deep  crescentic  arch. 

To  show  this  deep  arch  as  a  distinct  fascia,  there 
is  a  great  deal  of  dissection  required,  and  it  may  very 
justly  be  criticised  as  one  of  the  tricks  of  the  dis- 
sector; but  as  it  is  a  point  of  anatomy  which  is  often 
talked  of,  we  shall  describe  what  appears  to  us  to  be 
the  easiest  mode  of  displaying  it.  It  may  be  shown 
on  the  same  limb  in  which  the  anatomy  of  inguinal 
hernia  has  been  seen,  but  it  would  be  better  to  have 
another,  and  then  we  may  proceed  thus: — after  having 
made  the  dissection  of  the  external  oblique,  and  of  the 
superficial  crescentic  arch,  in  the  manner  already  de- 
scribed; we  should  hold  up  the  flap  of  the  external 
oblique,  and  dissect  between  it  and  the  internal  as 
far  down  as  the  edge  of  Poupart's  ligament.  The 
ligament  is  then  to  be  divided  into  two  laminae,  by 
forcing  the  handle  of  a  knife  between  the  point  of 
union  of  the  external  and  internal  oblique  with  it;  by 


GUIDE    TO    ANATOMY*  37 

pushing  the  knife  towards  the  thigh,  it  will  pass  under 
the  fascia  lata;  then  by  moving  it  in  a  horizontal  direc* 
tion  between  the  pubes  and  ilium.,  the  external  oblique 
and  fascia  lata,  which  are  connected  together  through 
the  medium  of  the  superficial  part  of  Poupart's  liga- 
ment, will  be  so  completely  separated  from  the  parts 
below,  that  the  ligament  will  appear  to  be  formed  by 
them  only.  But  if  we  cut  through  the  attachment  of 
the  ligament  to  the  superior  anterior  spinous  process 
of  the  ilium,  and  through  the  fascia  lata  as  far  down 
as  the  crescentic  arch,  (to  save  the  parts  below,  it  is 
useful  to  keep  the  handle  of  the  knife  under  the  fascia, 
as  a  directory  to  cut  upon,)  we  shall  then  have  a 
view  very  similar  to  that  we  have  just  destroyed, 
for  we  shall  see  that  the  deep  crescentic  fascia  has 
nearly  the  same  form  as  the  superficial  arch.  This 
deep  arch  may  be  described  as  being  formed  on  the 
iliac  side  of  the  vessels,  by  a  connection  between  the 
fascia  iliaca  and  the  obliquus  internus  and  transver- 
salis,  and  part  of  Poupart's  ligament;  and  on  the  pubic 
side,  by  the  fascia  transversalis,  in  union  with  the 
insertions  of  the  tendons  of  the  two  muscles  into 
the  linea  ileo-pectinea.  But  this  we  shall  more  fully 
comprehend  by  examining  the  parts  from  within.  On 
looking  into  the  pelvis,  we  see  the  artery  and  vein, 
surrounded  by  a  proper  sheath,  lying  upon  the  iliac 
fascia,  which  is  the  name  given  to  that  which  covers 
the  iliacus  internus  and  psoas  magnus.  If  we  hold 
up  the  part  of  the  abdominal  muscles  which  has  been 
left,  and  look  under  them  towards  the  thigh,  we  shall 
see  an  opening  like  the  mouth  of  a  funnel,  into  which 
the  vessels,  surrounded  by  their  sheath,  pass.  The 
posterior  boundary  of  this  space  may  be  described  as 
formed  by  a  prolongation  from  the  fascia  iliaca,  and 
from  which,  for  a  certain  space,  the  vessels  can  be 
easily  separated.  The  anterior  boundary  may  be 
traced  from  the  fascia  transversalis;  being  in  fact,  that 
4 


38  LONDON    DISSECTOR,  OR 

which  is  in  close  connection  with  the  ahdominal 
muscles,  and  forms  part  of  that  which  has  been  called 
the  deep  crescentic  arch.  At  a  short  distance  below 
Poupart's  ligament,  the  fascia  iliaca  and  transversalis 
become  so  closely  connected  with  each  other,  and 
with  the  cellular  membrane  which  forms  the  sheath 
of  the  vessels,  that  they  cannot  be  traced  farther 
down  upon  the  thigh. 

The  space  which  has  just  been  described  as  bounded 
by  the  fascia  iliaca  and  fascia  transversalis,  has  re- 
ceived various  names;  by  many  surgeons  it  has  been 
called  the  crural  sheath,*  by  others,  the  sheath  of  the 
vessels;  and  consequently,  when  the  latter  describe 
femoral  hernia,  they  say  that  it  passes  along  the  sheath 
of  the  vessels;  but  this  language  is  very  incorrect,  and 
leads  to  great  confusion,  for  the  proper  sheath  of  the 
vessels  is  a  distinct  part,  formed  by  cellular  mem- 
brane, which  surrounds  them  through  their  whole 
course  from  the  sacrum  to  the  point  where  the  pro- 
funda  is  given  off. 

M.  Cloquet  gives  the  description  of  this  part  too 
much  in  the  spirit  of  a  modern  discoverer  of  fasciae 
and  rings.  He  says  that  we  have  here  a  part  analo- 
gous to  the  inguinal  canal;  that  this  (the  crural  canal) 
"has  a  superior  and  inferior  opening.  The  inferior 
is  the  opening  by  which  the  saphena  passes  through 
the  fascia  lata  to  enter  the  femoral  vein."  Although 
this  opening  is  represented  in  all  the  plates  of  the 
anatomy  of  the  groin,  given  by  our  own  authors,  yet 
we  have  not  described  it,  because  we  think  that  it  is 
not  of  importance,  in  considering  femoral  hernia, — 
not  on  account  of  its  situation,  but  because  the  con- 
nection which  there  is  between  the  fascia  superficial 
and  the  lymphatic  glands,  prevents  a  femoral  hernia 

*  There  is  no  crural  ring  in  the  natural  state  of  the  parts,  but  it  may 
be/eZJ  during  an  operation;  and  a  distinct  ring  may  be  shown  in  a  pre- 
paration,  by  removing  the  whole  of  the  herniary  sac.  Such  an  appear- 
ance is  very  well  shown  in  Mr.  Cooper's  plates. 


GUIDE    TO    ANATOMY.  39 

from  passing  so  low  down.  There  are  no  cases  given 
by  English  authors,  of  hernia  protruding  through  this 
hole,  but  M.  Cloquet  says,  that  he  and  M.  Beclard, 
have  seen  many  examples  of  it: 


SECTION     III. 

Dissection  of  the  Cavity  of  the  Jlbdomen. 

THE  abdomen  is  divided  into  three  regions,  each 
of  which  is  again  sub-divided. 

1.  The  EPIGASTRIC,  or  upper  region,  includes  the 
part  covered  at  the  side  by  the  ribs;  its  lateral  por- 
tions are  named  the  right  and  left  HYPOCHONDRIA, 
and  its  central,  the  scrobiculus  cordis. 

2.  The  UMBILICAL,  or  middle  region,  is  the  space 
immediately  under  the  former;  and  it  extends  below 
to  the  anterior  superior  spines  of  the  ilia.     Its  sides 
are  called  the  lumbar  or  iliac  regions. 

3.  The  HYPOGASTRIC,  or  lowest  region,  is  sub- 
divided into  three  parts,  one  middle,  termed  REGIO 
PUBIS,  and  two  lateral,  named  INGUINAL  regions. 

Before  you  disturb  the  viscera,  observe  the  general 
situation  of  those  parts  which  appear  on  first  opening 
the  abdomen. 

1 .  The  internal  surface  of  the  PERITONEUM,  smooth, 
shining,  and  colorless,  covering  the  parietes  of  the 
abdomen,  and  the  surface  of  all  the  viscera. 

2.  In  the  triangular  portion  formed  by  two  ima- 
ginary lines  drawn  from  the  anterior  spinous  process 
of  the  ilium  to  the  umbilicus,  three  ligamentous  cords 
projecting  through  the  peritoneum,  two  running  late- 
rally, and  the  other  in  the  middle,  towards  the  navel. 
These  are  the  remains  of  the  two  umbilical  arteries 
and  the  urachus. 


40  LONDON    DISSECTOR,  OR 

3.  The   epigastric   artery,  accompanied   by  two 
veins,  may  be  seen  through  the  peritoneum,  ascend- 
ing obliquely  upwards  and  inwards  from  under  Pou- 
part's  ligament. 

4.  The  upper  edge  of  the  liver  is  seen  extending 
from   the   right  hypochondriac    region,   across   the 
epigastric,  into  the  left  hypochondriac  region:  in  it 
a   fissure   is  seen,  into  which   enters,  inclosed  in  a 
duplicature    of   peritoneum,   the   ligamentum  teres, 
which  was,  in  the  foetus,  the  umbilical  vein.     The 
fundus  of  the  gall-bladder,  if  distended,  is  sometimes 
seen  projecting  from  under  the  edge  of  the  liver. 

5.  The  STOMACH  will  be  found  lying  in  the  left 
hypochondriac  region,  and  upper  part  of  the  epigas- 
tric; but,  if  distended,  it  protrudes  into  the  umbilical 
region. 

6.  The  GREAT  OMENTUM,  or  onientum  majus,  pro- 
ceeds from  the  great  curvature  of  the  stomach,  and 
is  spread  like  an  apron  over  the  intestines. 

7.  The  GREAT  TRANSVERSE  ARCH  OF  THE  COLON 
will  be   seen   projecting  through   the   omentum;   it 
ascends  from  the  os  ilium  of  the  right  side,  crosses  the 
belly  under  the  edge  of  the  liver,  and  under  the 
greater  curvature  of  the  stomach,  and  descending 
again  upon  the  left  side,  sinks  under  the  small  intes- 
tines, and  rests  upon  the  wing  of  the  left  os  ilium. 

8.  The  SMALL  INTESTINES  lie  convoluted  in  the 
lower  part  of  the  belly,  surrounded  by  the  arch  of 
the  colon. 

Such  is  the  general  appearance  on  first  opening  the 
abdomen;  this  will  vary,  however,  as  one  intestine 
may  happen  to  be  more  inflated  than  another,  or 
according  to  the  position  of  the  body  after  death. 
But  to  consider  the  parts  more  minutely: 
1.  The  PERITONEUM. — Observe  how  it  is  reflected 
from  the  parietes  of  the  abdomen  over  all  the  viscera, 
so  that  they  may  be  said  to  be  situated  behind  it; 


GUIDE    TO    ANATOMY.  41 

trace  its  reflections  from  side  to  side,  and  from  above 
downwards;  you  will  see  that  the  external  coat  of 
every  viscus,  and  all  the  connecting  ligaments,  are 
reflections  or  continuations  of  this  membrane. 

(1.)  The  FOUR  LIGAMENTS  of  the  LIVER  are  form- 
ed by  the  peritoneum,  continued  from  the  diaphragm 
and  parietes  of  the  abdomen. 

a,  The  MIDDLE  or  SUSPENSORY  LIGAMENT,  inclos- 
ing in  its  duplicature  the  LIGAMENTUM  TERES. 

6,  The  CORONARY  LIGAMENT,  connecting  the 
upper  surface  of  the  liver  to  the  diaphragm. 

c,  The  BROAD  LIGAMENT  of  the  right  side. 

d,  The  BROAD  LIGAMENT  of  the  left  side. 

(2.)  The  LESSER  OMENTUM,  or  EPIPLOON,  or  the 
MESOGASTRION,  is  formed  by  two  laminae  of  perito- 
neum, passing  from  the  under  surface  of  the  liver  to 
the  less  curvature  of  the  stomach,  and  containing 
in  its  duplicature  the  vessels  of  the  liver. 

(3.)  The  GREAT  EPIPLOON  or  OMENTUM. — Ob- 
serve, that  the  peritoneum,  coming  from  both  sur- 
faces of  the  stomach,  and  from  the  spleen,  proceeds 
downwards  into  the  abdomen,  and  is  then  reflected 
back  upon  itself,  till  it  reaches  the  transverse  arch  of 
the  colon,  where  its  laminae  separate  to  invest  that 
intestine.  This  reflection  is  named  the  Great  Omen- 
turn;  it  is  a  pouch  or  bag,  composed  of  four  laminae 
of  peritoneum,  and  the  opening  into  it  is  by  the  FO- 
RAMEN of  WINSLOW:  Observe  the  situation  of  this 
semilunar  opening;  it  is  on  the  right  side  of  the  abdo- 
men, at  the  root  of  the  less  lobe,  or  lobulus  spigelii 
of  the  liver;  it  leads  under  the  little  epiploon,  under 
the  posterior  surface  of  the  stomach,  but  above  the 
pancreas  and  colon,  into  the  sac  of  the  omentum; — 
the  omentum  sometimes  reaches  to  the  lower  part  of 
the  hypogastric  region,  sometimes  not  beyond  the 
navel;  it  contains  in  its  duplicature  more  or  less  of 
adipose  substance. 
4* 


42  LONDON    DISSECTOR,  OR 

(4.)  The  MESENTERY. — Observe,  that  the  perito- 
neum, reflected  from  each  side  of  the  vertebrae,  pro- 
ceeds forward,  to  connect  the  intestines  loosely  to  the 
spine;  that  it  begins  opposite  to  the  first  lumbar  ver- 
tebra, crosses  obliquely  from  left  to  right,  and  ends 
half-way  between  the  last  lumbar  vertebra  and  the 
groin.  At  its  commencement,  it  binds  down  the 
extremity  of  the  duodenum,  and  terminates  where  the 
head  of  the  colon  begins.  The  great  circumference 
which  is  in  contact  with  the  intestines,  is  very  much 
plaited  or  folded,  and  is  several  yards  in  length. 
Between  the  laminae  of  mesentery,  observe  the  CON- 
GLOBATE GLANDS,  less  numerous  in  old  age:  the 
branches  of  the  superior  mesenteric  artery  ramifying 
and  forming  arches;  the  mesenteric  veins  accompa- 
nying the  arteries;  the  trunk  of  the  lacteals,  situated 
contiguous  to  the  mesenteric  artery  on  its  left  side. 
It  may  sometimes  be  inflated  by  the  blow-pipe. 
Nerves  also  run  in  the  mesentery,  but  are  not  easily 
demonstrated. 

(5.)  The  MESOCOLON  is  similar  to  the  mesentery, 
and  connects,  in  like  manner,  the  colon  to  the  spine. 

2.  HEPAR,  the  LIVER. — Situation:  Partly  in  the 
right  hypochondrium,  which  it  fills  up,  reaching  as 
low  as  the  kidney  of  that  side,  partly  in  the  epigas- 
trium, and  running  also  some  way  into  the  left  hypo- 
chondrium. 

Connected  by  its  four  ligaments  to  the  inferior  sur- 
face of  the  diaphragm,  and  by  the  smaller  epiploon  to 
the  small  curvature  of  the  stomach: — The  little 
epiploon  should  now  be  removed,  to  discover  the 
different  parts  of  the  liver. 

Observe  its  superior  or  convex  surface  adapted  to 
the  arch  of  the  diaphragm;  the  inferior  or  concave 
surface  resting  on  the  stomach; — the  posterior  or 
thick  edge  lying  against  the  vertebrae,  and  the  anterior 
thin  margin  corresponding  to  the  lower  edge  of  the 


GUIDE   TO   ANATOMY.  43 

chest; — Observe  the  three  lobes  of  the  liver; — the 
great  or  right  lobe; — the  small  or  left  lobe; — the  lobu- 
lus  spigelii; — the  great  fissure,  separating  the  right 
and  left  lobe,  and  receiving  the  suspensory  ligament, 
and  the  ligamentum  teres; — the  cavity  of  the  portae 
between  the  great  lobe  and  lobulus  spigelii; — the  fis- 
sure on  the  right  side  of  the  lobulus  for  the  vena  cava 
inferior,  which  fissure  is  almost  a  complete  foramen; 
the  notch  in  the  back-part  for  the  vertebrae; — the 
depression  in  the  right  lobe  for  the  gall-bladder. 
Observe  the  vessels  in  the  cavity  of  the  portae,  the 
hepatic  artery  on  the  left  side,  the  ductus  communis 
choledochus  on  the  right  side,  and  betwixt,  but  at  the 
same  time  behind  them,  the  vena  portae;  they  are  all 
surrounded  by  a  plexus  of  nerves.  These  vessels 
and  nerves  pass  along  the  edge  of  the  mesogaster,  or 
little  omentum,  surrounded  and  connected  by  adipose 
and  cellular  substance;  the  part  is  called  CAPSULA 
GLISSONI.  Observe  that  the  ligamentum  teres  was 
the  umbilical  vein  of  the  foetus,  entering  the  vena 
portae,  and  that  the  ductus  venosus  in  the  foetus  (ob- 
literated in  the  adult,)  leaving  the  vena  portae,  passed 
into  one  of  the  venae  cavae  hepaticae. 

3.  VESICULA  FELLIS,  the  GALL-BLADDER. — Situa- 
tion-.  In  the  right  hypochondrium,  in  a  superficial 
depression  on  the  under  surface  of  the  right  lobe  of  the 
liver;  it  sends  off  the  DUCTUS  CYSTICUS,  which,  unit- 
ing with  the  DUCTUS  HEPATICUS,  forms  the  DUCTUS 
COMMUNIS  CHOLEDOCHUS;   this  perforates  the  first 
curvature  of  the  duodenum. 

4.  VENTRICULUS,  the  STOMACH. — Situation:  In  the 
left  hypochondriac  and  epigastric  regions:  Connected, 
to  part  of  the  inferior  surface  of  the  diaphragm,  to 
the  concave  surface  of  the  liver  by  the  little  epiploon, 
to  the  spleen  by  a  reflection  of  peritoneum,  and  to 
the  arch  of  the  colon  by  the  great  omentum.     Ob- 
serve its  greater  curvature  looking  downwards,  its 


44  LONDON    DISSECTOR,  OR 

less  curvature  looking  upwards;  and  its  two  lateral 
surfaces.  Observe  the  bulging  extremity  on  the  left 
side,  the  cardia  or  upper  orifice,  where  the  oesopha- 
gus enters,  and  the  pylorus,  or  lower  orifice,  at  the 
end  of  the  small  extremity. 

5.  The  INTESTINES. — They  are  divided  into  two 
classes,  the  small  and  the  large. 

The  small  intestines  are  again  subdivided  into  the 
duodenum,  jejunum,  and  ileon;  the  large  into  caecum, 
colon  and  rectum. 

(1.)  SMALL  IMTESTINES. — They  are  about  four 
times  as  large  as  the  body. 

a,  The  DUODENUM  is  broader  than  any  other  part 
of  the  small  intestines,  but  is  exceedingly  short:  leav- 
ing the  pylorus  it  passes  upwards,  under  the  liver  and 
gall-bladder;  and  turning  upon  itself,  it  descends,  as 
low  as  the  right  kidney;  in  which  space  it  receives 
the  pancreatic  and  cystic  ducts;  it  then  crosses  before 
the  renal  vessels  and  the  aorta,  and  being  firmly 
bound  down  by  the  peritoneum,  upon  the  last  vertebra 
of  the  back,  it  ascends  from  right  to  left,  till  it  is  lost 
under  the  root  of  the  mesocolon. 

By  turning  back  the  colon  and  omentum,  over  the 
brim  of  the  thorax,  and  pushing  down  the  small  intes- 
tines towards  the  pelvis,  you  find  the  duodenum  com- 
ing out  from  under  the  mesocolon,  but  still  tied  close 
to  the  spine;  it  terminates  in  the  jejunum,  exactly 
where  the  mesentery  begins. 

6,  The  JEJUNUM  constitutes  the  first  or  upper  half 
of  the  remaining  small  intestines,  and  is  situated  more 
in  the  upper  part  of  the  abdomen;  it  is  redder,  and 
its  coats  feel  thicker  to  the  touch,  from  the  greater 
number  of  the  valvulas  conniventes  on  its  inner  sur- 
face; and  its  diameter  exceeds  that  of  the  ileon. 

c,  The  lower  half  is  named  ILEON;  it  is  situated 
more  in  the  lower  part  of  the  abdomen,  and  termi- 


GUIDE    TO    ANATOMY.  45 

nates  in  the  great  intestine,  by  entering  the  caput  coli, 
or  beginning  of  the  colon. 

The  course  of  the  canal,  independently  of  its  con- 
volutions, is  from  the  left  lumbar  region,  where  the 
duodenum  emerges  from  under  the  mesocolon  to  the 
right  inguinal  region,  where  the  ileon  terminates  in 
the  caput  coli. 

(2.)  The  divisions  of  the  great  intestines. 

d,  The  C^CUM,  or  blind  gut,  is  tied  down  by  the 
peritoneum  to  the  loins  on  the  right  side,  lying  in  the 
space  under  the  right  kidney,  and  hid  by  the  convo- 
lutions of  the  ileon.     On  its  posterior  part  there  is  a 
little  appendage,  of  the  shape  of  an  earth-worm, 
named  Appendix  Cazci  Vermiformis. 

e,  The  COLON. — Its  commencement  at  the  caecum 
is  termed  CAPUT  COLI,  or  head  of  the  colon;  it  passes 
from  the  caecum  over  the  right  kidney,  to  which  it  is 
connected  by  cellular  substance,  and  having  passed 
under  the  gall-bladder,  which,  after  death,  tinges  it 
with  bile,  it  goes  across  the  upper  part  of  the  belly, 
forms  the  GREAT  TRANSVERSE  ARCH.     In  its  whole 
course  it  is  contracted  into  cells  by  its  muscular 
fibres,  which  are  united  together,  forming  longitudinal 
bands;  and  to  its  surface  are  attached  some  fatty  pro- 
jections named  Appendices  Epiploica3.     These  two 
circumstances   may  distinguish   the  large   from  the 
small  intestines;  more  than  their  difference  of  size. 
For  when  the  large  intestine  is  empty,  it  contracts, 
and  may  be  even  smaller  than  the  small;  but  if  it  were 
inflated,  it  could  be  distended  to  a  much  greater 
degree.     The  colon  then  passes  backwards  under 
the  stomach  and  spleen  into  the  left  hypochondrium; 
and  descending  over  the  left  kidney,  it  is  again  tied 
down;  finally  it  turns  over  the  brim  of  the  pelvis, 
being  at  this  part  unconfined,  and  forming  a  loose  and 
remarkable  curvature,  which  is  named  the  SIGMOID 
or  ILIAC  FLEXURE,  terminates  in 


46  LONDON    DISSECTOR,  OR 

The  RECTUM. — Which  descends  along  the  anterior 
surface  of  the  sacrum  and  os  coccygis  to  the  anus. 

By  drawing  the  stomach  towards  the  right  side, 
you  will  expose, 

6.  The  LIEN,  or  SPLEEN. — Situation:  In  the  left 
hypochondriac  region,  between  the  great  extremity 
of  the  stomach,  and  the  neighbouring  false  ribs,  under 
the  edge  of  the  diaphragm,  and  above  the  left  kid- 
ney; to  all  of  which  it  is  connected  by  the  perito- 
neum.    It  is  of  an  oval  figure;  slightly  convex  on  its 
external  and  irregularly  concave  on  its  internal  sur- 
face, and  divided  by  a  longitudinal  fissure,  into  which 
its  vessels  enter. 

7.  The  PANCREAS. — This  gland  was  in  part  seen 
on  removing  the  little  epiploon;  it  is  more  fully 
exposed,!by  tearing  through  the  great  epiploon  between 
the  great  curvature  of  the  stomach,  and  the  transverse 
arch  of  the  colon.     It  lies  in  the  cavity  into  which 
the  foramen  of  Winslow  leads;  it  extends  from  the 
fissure  of  the  spleen  across  the  spine,  under  the  pos- 
terior surface  of  the  stomach,  and  terminates  within 
the  circle  formed  by  the  duodenum;  it  is  only  covered 
on  its  anterior  surface  by  the  peritoneum. 

The  PANCREATIC  DUCT  pierces  the  coats  of  the 
duodenum,  and  enters  the  cavity  of  that  intestine,  by 
an  orifice  common  to  it,  and  to  the  ductus  communis 
choledochus.  The  duct  runs  along  the  very  centre 
of  the  gland,  where  the  whiteness  of  its  coats  will 
readily  enable  the  student  to  distinguish  it. 

All  the  abdominal  viscera  may  now  be  removed, 
except  the  rectum,  where  it  descends  into  the  pelvis, 
which,  being  tied,  should  be  allowed  to  remain,  for  it 
belongs  to  the  demonstration  of  those  parts:  or  the 
liver  and  its  vessels,  with  the  pancreas,  may  be  left; 
and  the  vessels  entering  the  portae  of  the  liver  traced. 

The  peritoneum  should  now  be  carefully  dissected 
from  the  diaphragm,  and  from  the  sides  and  back-part 


GUIDE    TO    ANATOMY.  47 

of  the  abdomen,  that  the  parts  which  lie  more  imme- 
diately behind  that  membrane  may  be  examined. 

8.  RENES,  the  KIDNEYS.  Two  glandular  bodies, 
situated  in  the  posterior  part  of  the  abdominal  cavity, 
one  on  each  side  of  the  lumbar  vertebrae,  between  the 
last  false  rib  and  the  spine  of  the  ilium,  and  imbed- 
ded in  a  quantity  of  adipose  membrane. 

Each  kidney  has  a  concavity  turned  obliquely  for- 
wards and  inwards;  and  is  convex  obliquely  back- 
wards and  outwards;  its  superior  extremity  is  nearer  to 
that  of  the  opposite  kidney  than  the  inferior.  Observe 
the  renal  or  emulgent  artery  entering  the  concave  sur- 
face, and  the  vein  and  ureter  passing  out.  Notice  the 
course  of  the  ureter;  it  passes  behind  the  peritoneum 
over  the  psoas  muscle  into  the  pelvis,  and  running 
between  the  rectum  and  bladder,  penetrates  the  latter. 

9.  The  CAPSULE  RENALES. — Are  two  glandular 
bodies  situated  on  the  upper  extremity  of  each  kid- 
ney, their  figure  is  irregular,  crescent-like,  or  some- 
what triangular. 

By  the  removal  of  the  peritoneum,  several  muscles 
are  exposed,  situated  at  the  superior  and  posterior 
parts  of  the  abdomen. 

DlAPHRAGMA,    the    DlAPHRAGM,     Or     MlDRIFF. 

This  is  a  broad,  thin,  muscular  septum  between  the 
thorax  and  abdomen;  it  is  concave  below,  and  convex 
above,  the  middle  of  it  on  each  side  reaching  as  high 
within  the  thorax  as  the  fourth  rib.  It  is  divided  into 
two  portions: 

1.  The  superior  or  greater  muscle  of  the  dia- 
phragm, forms  the  transverse  partition  between  the 
chest  and  abdomen, 

Jlrising,  by  distinct  fleshy  fibres,  1 .  From  the  pos- 
terior surface  of  the  ensiform  cartilage;  2.  From  the 
cartilages  of  the  seventh,  and  all  the  false  ribs;  3. 
From  the  ligamentum  arcuatum,  which  is  a  ligament 
extending  from  the  top  of  the  twelfth  rib  to  the  lum- 


48  LONDON   DISSECTOR,  OR 

bar  vertebrae,  forming  an  arch  over  the  psoas  and 
quadratus  lumborum  muscles.  The  fibres  run,  in  dif- 
ferent directions,  like  radii  from  the  circumference  to 
the  centre  of  a  circle,  and  are 

Inserted  into  a  broad  tendon  (tendinous  centre,  or 
cordiform  tendon,)  which  is  situated  in  the  middle  of 
the  diaphragm,  and  in  which,  therefore,  the  fibres 
from  the  opposite  sides  are  interlaced. 

2.  The  inferior  or  less  muscle,  or  appendix  of  the 
diaphragm,  lies  on  the  bodies  of  the  vertebrae,  and 

Arises,  by  four  small  tendinous  feet,  on  each  side, 
from  the  second,  third,  and  fourth  lumbar  vertebrae; 
these  tendons  soon  join,  to  form  a  strong  pillar  on 
each  side,  named  the  Crus  of  the  Diaphragm.  The 
crura  run  obliquely  upwards  and  forwards,  form  too 
fleshy  bellies,  a  fasciculus  of  each  of  which  crossing 
over  to  the  other,  decussates  with  the  opposite  one, 
and  thus  forms  the  interval  of  the  two  crura  into  a 
superior  and  inferior  opening. 

Inserted  into  the  posterior  part  of  the  middle  cor- 
diform tendon. 

Situation:  The  diaphragm  is  perforated  in  its  fleshy 
and  tendinous  parts  by  several  blood-vessels,  and 
other  important  organs. 

(1.)  The  aorta  lying  close  upon  the  spine  passes 
between  the  tendinous  part  of  the  crura;  and  the  tho- 
racic duct  passes  betwixt  the  orta  and  the  right  cms. 

(2.)  A  little  above,  and  to  the  left  side  of  the  aorta, 
the  oesophagus,  with  the  eighth  pair  of  nerves  attached 
to  it,  passes  through  an  oval  fissure  formed  in  the 
fleshy  columns  of  the  inferior  muscle.  These  two 
parts  are  separated  by  the  decussating  fasciculi  just 
described. 

(3.)  The  vena  cava  perforates  the  tendon  towards 
the  right  side  by  a  triangular  hole. 

(4.)  The  posterior  intercostal  nerve,  and  branches 
of  the  vena  azygos,  perforate  some  of  the  posterior 


GUIDE    TO    ANATOMY.  49 

fibres  of  the  crura: — The  splanchnic,  or  anterior 
intercostal  nerve,  also  passes  through  an  opening  in 
the  substance  of  the  crura. 

(5.)  On  each  side  of  the  sternum  there  is  a  small 
fissure,  where  the  peritoneum  and  pleura  are  only 
separated  by  adipose  membrane. 

Use:  The  diaphragm  is  one  of  the  chief  agents  in 
respiration;  it  also  acts  in  coughing,  laughing,  and 
speaking,  and  in  the  expulsion  of  the  urine  and  faeces. 

The  muscles  situated  within  the  posterior  part  of 
the  abdominal  cavity  are  four  on  each  side. 

1 .  THE  PSOAS  PARVUS. — It  arises,  fleshy,  from  the 
sides  of  the  last  dorsal,  and  first  lumbar  vertebra;  it 
sends  off  a  small  long  tendon,  which,  running  on  the 
inside  of  the  psoas  magnus,  is 

Inserted,  thin  and  flat,  into  the  brim  of  the  pelvis, 
at  the  junction  of  the  os  ilium  and  pubis. 

This  muscle  lies  on  the  anterior  part  of  the  loins, 
betwixt  the  psoas  magnus  and  the  vertebras;  some- 
times, however,  it  is  wanting. 

2.  THE  PSOAS  MAGNUS. — It  is  situated  between  the 
psoas  parvus  and  iliacus  internus.     It   arises,  fleshy, 
from  the  side  of  the  body,  and  transverse  process  of 
the  last  vertebra  of  the  back,  and  in  the  same  manner 
from  all  those  of  the  loins,  by  as  many  distinct  slips. 
It  runs  down  over  the  brim  of  the  pelvis,  and  is 

Inserted,  tendinous,  into  the  trochanter  minor  of  the 
os  femoris,  and  fleshy,  into  that  bone  immediately 
below  the  trochanter. 

3.  The  ILIACUS  INTERNUS. — This  muscle  fills  up 
the  internal  concave  surface  of  the  os  ilium.    It  arises, 
fleshy,  from  the  transverse  process  of  the  last  lumbar 
vertebra,  from  all  the  inner  margin  of  the  spine  of  the 
os  ileum,  from  the  edge  of  that  bone  between  its 
anterior  superior  spinous  process  and  the  acetabulum, 
and  from  all  its  hollow  part  between  the  spine  and  the 
linea  innominata.    Its  fibres  descend  under  the  outer 

5 


50  LONDON    DISSECTOR,  &C. 

half  of  Poupart's  ligament,  and  join  the  tendon  of  the 
psoas  magnus. 

Inserted  with  the  psoas  magnus  into  the  trochanter 
minor.  This  muscle  is  covered  by  a  pretty  strong 
fascia,  which  is  inserted  into  the  crista  of  the  ilium, 
and  into  the  crural  arch:  the  FASCIA  ILIACA.  The 
latter  insertion  prevents  the  bowels  from  descending 
under  Poupart's  ligament,  except  at  the  inner  edge  of 
the  iliac  vein,  which  is  accordingly  the  situation  of 
the  crural  hernia,  and  which  the  student  should  exam- 
ine most  carefully.  A  part  of  this  fascia  is  also 
continued  behind  the  femoral  vessels  over  the  pubis, 
to  form  a  part  of  the  sheath  which  incloses  those 
vessels. 

4.  The  QUADRATUS  LUMBORUM. — This  muscle 
arises,  tendinous  and  fleshy,  from  rather  more  than  the 
posterior  third  of  the  spine  of  the  os  ilium. 

Inserted  into  the  transverse  processes  of  all  the  ver- 
tebras of  the  loins,  the  posterior  half  of  the  last  rib, 
and,  by  a  small  tendon,  into  the  side  of  the  last  ver- 
tebra of  the  back. 

It  is  situated  laterally  at  the  lower  part  of  the  spine, 
more  outwardly  than  the  psoas  magnus,  between  the 
origin  of  the  psoas  and  the  transversalis  abdominis. 


CHAP  TER    II. 

DISSECTION   OF   THE   PERINEUM  AND  OF 
THE  MALE  ORGANS  OF  GENERATION. 


THE  muscles  to  be  demonstrated  being  imbedded 
in  loose  cellular  substance,  are  to  be  dissected  with 
great  caution.  The  Rectum  having  been  cleansed, 
hair  may  be  introduced  into  its  extremity,,  to  keep  the 
anus  gently  protruding  during  the  dissection;  or  a 
cork,  with  a  loop  attached  to  it,  may  be  introduced, 
and  the  mouth  of  the  gut  tied  upon  it; — this  last  method 
is  preferable,  as  the  intestine  can  then  be  turned  in 
every  direction.  To  facilitate  the  dissection  introduce 
a  staff  into  the  bladder,  to  mark  out  the  situation  of 
the  urethra;  and  place  the  subject  in  the  same  position 
as  for  the  lateral  operation  of  lithotomy. 

The  muscles  of  the  perineum  consist  of  five  pair, 
and  a  single  muscle: 

ERECTOR  PENIS, 


ACCELERATOR  URINJE, 
TRANSVERSUS  PERIN^SI, 
LEVATOR  ANI, 


SPHINCTER 

ANI,  single 
muscle. 


COCCYGEUS. 

In  commencing  this  important  dissection,  recollect 
that  the  erector  muscle,  covering  the  crus  of  the 
penis,  arises  from  the  tuber  ischii,  and  ascends  on  the 
inside  of  the  ramus  of  that  bone, — that  the  transversus 
perinei  arises  from  nearly  the  same  point,  and  crosses 
the  perineum,  lying  often  at  a  considerable  depth  in 
the  adipose  substance.  The  tuber  ischii  then  be- 
comes a  proper  place  for  the  commencement  of  the 


52  LONDON    DISSECTOR,  OR 

dissection;  carefully  tracing  the  muscles  arising  from 
that  point,  remove  all  the  cellular  substance,  situated 
in  the  perineum,  while  the  muscular  fibres  are  left 
untouched;  the  RAPHE  or  line  running  along  the  skin 
of  the  perineum,  marks  the  place  where  the  opposite 
muscles  meet.  The  appearance  of  these  muscles 
will  vary  in  different  subjects.  In  the  weak  and 
emaciated,  the  fibres  will  be  pale,  and  not  very  evi- 
dent, while  in  strong  muscular  men,  who  have  expired 
suddenly,  they  will  be  very  distinct.  This  dissection 
is  to  be  continued  till  all  the  parts  between  the  tube- 
rosities  of  the  ischia  on  each  side,  and  between  the 
pubis  before,  and  the  tip  of  the  os  coccygis  behind, 
are  fairly  brought  into  view.  Observe 

The  ERECTOR  PENIS  covering  the  crus  of  the 
penis. 

The  ACCELERATOR  URIN^E  embracing  the  bulb 
and  lower  part  of  the  CORPUS  SPONGIOSUM  of  the 
urethra. 

The  SPHINCTER  ANI,  encircling  the  anus. 

The  TRANSVERSUS  PERINJEI,  crossing  the  perineum 
transversely. 

1.  The   ERECTOR  PENIS — Arises ,  tendinous   and 
fleshy,  from  the  tuberosity  of  the  os  ischium;   its 
fleshy  fibres  proceed  upwards  over  the  crus  of  the 
penis,  adhering  to  the  outer  and  inner  edges  of  the 
ascending  ramus  of  the  os  ischium,  and  of  the  de- 
scending ramus  of  the  os  pubis; — but  before  the  two 
crura  meet  to  form  the  body  of  the  penis,  it  ends  in 
a  flat  tendon,  which  is  lost  in  the  strong  tendinous 
membrane  that  covers  the  corpus  cavernosum. 

2.  THE  ACCELERATOR  URINES — Arises,  by  a  thin 
tendinous  expansion,  from  the  descending  ramus  of 
the  pubis,   and  from  the  ascending  ramus   of  the 
ischium,   nearly   as    far   down    as    the    tuber;    the 
fleshy  fibres  are  seen  coming  out  from  the  angle 
between  the  crus  and  the  corpus  spongiosum  urethrae; 


GUIDE    TO    ANATOMY.  53 

they  proceed  obliquely  downwards  and  backwards, 
embrace  the  bulb  and  lower  part  of  the  corpus  spon- 
giosum,  and  are 

Inserted  into  a  white  tendinous  line  in  the  middle  of 
the  bulb  of  the  urethra,  joining  there  with  the  muscle 
of  the  opposite  side.  The  lowermost  fibres  run  nearly 
transversely,  while  the  superior  fibres  are  very  oblique. 

This  muscle,  called  also,  ejaculator  seminis,  forces 
the  urine  and  semen  forwards,  by  compressing  the 
lower  part  of  the  urethra,  and  propels  the  blood 
towards  the  corpus  spongiosum  and  the  glans  penis. 

3.  The  TRANSVERSUS  PERIN^I — Arises  from  the 
tough  fatty  membrane  that  covers  the  tuber  ischii, 
immediately  behind  the  attachment  of  the  erector 
penis;  thence  its  fibres  run  transversely  inwards. 

Inserted  into  the  central  point  of  union  where  the 
sphincter  ani  touches  the  accelerator  urinse,  and 
where  a  kind  of  tendinous  projection  is  formed,  com- 
mon to  the  five  muscles. 

Use:  This  muscle,  or  the  transversalis  penis  serves 
to  dilate  the  bulb  of  the  urethra,  to  prevent  the  anus 
from  being  too  much  protruded,  and  to  retract  it 
when  protruded. 

There  is  sometimes  another  slip  of  fibres,  the 
TRANSVERSUS  PERIN^EI  ALTER,  which  has  the  same 
course,  and  is  inserted  into  the  posterior  part  of  the 
bulb  of  the  urethra. 

4.  The  SPHINCTER  ANI  is  a  broad  circular  band 
of  fibres  which  surround  the  extremity  of  the  rectum, 
passing  nearly  as  far  out  as  the  tuber  ischii;  the  fibres 
of  each  side  decussate  where  they  meet. 

It  arises  from  the  extremity  of  the  os  coccygis  be- 
hind;* and  is  inserted  before  into  a  tendinous  point 

*The  sphincter  ani  often  arises  by  an  elastic  tendon,  approaching  to 
the  nature  of  a  ligament,  from  the  apex  of  the  os  coccygis.  This  tendon 
is  of  some  length;  it  gives  off  muscular  fibres,  which  surround  the 
extremity  of  the  rectum. 

5* 


54 

common  to  this  muscle,  and  to  the  acceleratores  urinse 
and  transversi  perinei.  This  tendinous  point  is  worthy 
of  remark;  it  seems  to  consist  in  part  of  an  elastic 
ligamentous  substance. 

It  closes  the  anus,  or  extremity  of  the  rectum,  and 
draws  down  the  bulb  of  the  urethra.  It  is  in  a  state 
of  constant  contraction,  independently  of  the  will,  in 
order  to  prevent  the  contents  of  the  rectum  from 
escaping  except  at  those  times  when  we  make  an 
effort  to  evacuate  them. 

More  deeply  seated  than  the  muscles  now  describ- 
ed, we  see  some  of  the  fibres  of 

The  LEVATOR  ANI. — This  muscle,  called  also 
Musculus  ani  Latus,  arises  from  the  inside  of  the  os 
pubis,  at  the  upper  edge  of  the  foramen  thyroideum, 
from  the  inside  of  the  os  ischium,  from  the  tendinous 
membrane  covering  the  obturator  internus  and  coccy- 
geus  muscles; — from  this  semicircular  origin  its  fibres 
run  down  like  radii  towards  a  centre,  and  are 

Inserted  into  tfie  two  last  bones  of  the  os  coccygis, 
and  the  verge  of  the  anus,  passing  within  the  fibres  of 
the  sphincter  ani,  but  on  the  outside  of  the  longitudinal 
fibres  of  the  gut  itself. 

This  muscle,  with  its  fellow,  Tery  much  resembles 
a  funnel,  surrounding  the  extremity  of  the  rectum,  the 
neck  of  the  bladder,  (which  passes  through  a  slit  in  its 
fibres,)  the  prostrate  gland,  and  part  of  the  vesiculae 
seminales. 

It  serves  to  draw  the  rectum  upwards  after  the 
evacuation  of  the  faeces,  to  assist  in  closing  it,  and  to 
compress  the  vesciculas  seminales,  and  other  viscera 
of  the  pelvis. 

6.  The  COCCYGEUS  arises,  tendinous  and  fleshy, 
from  the  spinous  process  of  the  os  ischium,  and  covers 
the  inside  of  the  posterior  sacro-sciatic  ligament;  it 
forms  a  thin  fleshy  belly. 


GUIDE   TO   ANATOMY.  55 

Inserted  into  the  extremity  of  the  os  sacrum,  and 
the  lateral  surface  of  the  coccygis,  immediately  before 
the  gluteus  maximus,  and  between  it  and  the  levator 
ani. 

It  supports  and  moves  the  os  coccygis  forwards, 
and  connects  it  more  firmly  with  the  sacrum. 

The  acceleratores  urinae  and  transversi  perinei  must 
now  be  removed  from  their  insertions.  They  may  be 
left  suspended  by  their  attachments  to  the  bone.  The 
rectum  must  be  separated  from  the  bladder,  and  pulled 
downwards.  This  dissection  will  expose  a  great 
part  of  the  levator  ani; — the  neck  and  body  of  the 
bladder; — the  prostrate  gland; — the  vesiculae  semina- 
les; — the  glandular  anteprostatae; — part  of  the  vasa 
deferentia;  part  of  the  ureters; — the  urethra,  its  mem- 
branous part,  its  bulb,  and  corpus  spongiosum; — the 
crura  penis,  and  their  origins  from  the  ischium; — 
Observe, 

1 .  The  connection  of  the  bladder  and  rectum,  and 
the  cellular  substance  interposed  between  them, 

2.  The  prostate  gland:  Situated  between  the  blad- 
der and  rectum,  surrounding  the  beginning  of  the 
urethra' in  such  a  manner,  that  one  third  of  its  thick- 
ness is  situated  above  the  urethra,   and  two-thirds 
below  it;  its  shape  is  somewhat  pyriform,  and  its 
consistence  between  cartilage  and  ligament. 

3.  The  URETHRA. — The  curve  should  be  carefully 
observed.     The  urethra  begins  at  the  neck  of  the 
bladder;  it  is  a  continuation  of  that  part  of  the  bladder 
which  in  the  erect  posture  is  lowest.     (1.)  Its  begin- 
ning is  imbedded  in  the  prostate  gland.     (2.)   Its 
membranous  part  is  very  short, — situated  between 
the   prostate  gland  and  bulb  of  the  urethra: — in  dis- 
secting, remark,  that  there  is  a  firm  fasciculus  of 
fibres  surrounding  it,  and  connecting  it  and  the  pros- 
tate gland  to  the  arch  of  the  pubis;  this  fasciculus 
gives  support  to  the  urethra,  and  is  termed  the  liga- 


56  LONDON   DISSECTOR,  OR 

mentum  triangulare  urethrae.  It  is  sometimes  described 
as  a  compressor  muscle  of  the  prostate  gland.  (3.) 
The  urethra  then  enters  the  corpus  spongiosum. 

4.  The  CORPUS   SPONGIOSUM  URETHRAS  consists 
of  a  plexus  of  minute  veins  covered  externally  by  a 
thin  but  uniform  tendinous  sheath;  it  surrounds  the 
urethra  from  a  short  distance  from  the  bladder  to  its 
extremity:  at  its  beginning,  it  forms  a  considerable 
body  of  a  pyriform  shape,  termed  the  Bulb  of  the 
Urethra;  that  part  of  the  bulb  which  is  below  the 
urethra,  is  named  the  pendulus  part  of  the  bulb..    The 
corpus  spongiosum  is  expanded  at  its  anterior  extre- 
mity, to  form  the  glans  penis. 

5.  The  GLANDULE  ANTEPROSTAT^:,  or  Cowper's 
Glands,  are  two  small  glands  of  the  size  of  peas,  situ- 
ated immediately  before  the  prostate,  and  between 
the  membranous  part  and  bulb  of  the  urethra. 

6.  The  VESICUL^E  SEMINALES  are  two  soft,  whitish, 
knotted  bodies,  about  three  or  four  fingers-breadth  in 
length,  and  one  in  breadth,  and  about  three  times  as 
broad  as  thick:  Situated  between  the  rectum  and  lower 
part  of  the  bladder  obliquely,  so  that  their  inferior 
extremities  are  contiguous,  and  are  affixed  to  the  base 
of  the  prostate  gland,  while  their  superior  extremities 
are  at  a  distance  from  each  other  extending  outwards 
and  upwards,  and  terminating  just  on  the  inside  of  the 
insertion  of  the  ureters  in  the  bladder. 

7.  The  two  VASA  DEFERENTIA  are  seen  running 
betwixt  the  vesiculae  seminales,  and  united  to  them  and 
to  the  base  of  the  prostate.     Observe  that  part  of  the 
bladder,  left  between  these  tubes,  and  connected  by 
cellular  substance  to  the  rectum,  which  is  pierced 
when  the  bladder  is  punctured  from  the  latter  part. 

8.  The  CORPORA    CAVERNOSA    PENIS  arise,  on 
each  side,  by  a  process  named  the  CRUS,  from  the 
ramus  and  tuber  ischii,  ascend  along  the  ischium  and 
pubis,  and  are  united  immediately  before  the  cartila- 


GUIDE    TO    ANATOMY.  57 

ginous  arch  of  the  pubis; — they  are  covered  by  a  strong, 
white,  shining,  fibrous,  ligamento-tendinous  substance, 
which  is  very  elastic.  Internally  they  are  cavernous, 
and  are  separated  from  each  other  by  a  septum,  which, 
from  being  perforated,  is  named  Septum  pectiniforme. 

By  the  union  of  the  corpora  cavernosa,  two  grooves 
are  formed: — (1.)  A  smaller  one  above,  in  which  two 
arteries  pass,  a  large  vein  or  two  betwixt  them,  and 
some  large  twigs  of  nerves.  (2.)  A  larger  groove 
below,  which  receives  the  urethra. 

9.  The  VESICA  URINARIA,  or  URINARY  BLADDER, 
is  situated  within  the  pelvis,  immediately  behind  the 
ossa  pubis,  and  before  the  rectum.  It  is  covered  on 
its  upper  and  back  part  by  a  reflection  of  peritoneum: 
in  front  and  below  (where  it  is  contiguous  to  the  rec- 
tum,) it  is  connected  by  cellular  membrane  to  the  sur- 
rounding parts.  Shape,  oval,  but  flattened  before  and 
behind,  and,  while  in  the  pelvis,  somewhat  triangular. 
Divided  into  the  fundus  or  bottom,  corpus  or  body, 
and  cervix  or  neck.  In  the  contracted  state,  the  fundus 
is  the  broadest  and  roundest  part,  but,  when  distended, 
the  cervix  is  broader  than  any  other  part.  At  the  top 
of  the  bladder,  above  the  symphysis  pubis,  may  be 
observed,  the  superior  ligament  of  the  bladder,  con- 
sisting of  the  Urachus,  a  ligamentous  cord,  which  runs 
up  between  the  peritoneum  and  linea  alba,  as  far  as  the 
navel,*  and  two  of  the  ligamentous  cords,  which  are 
the  remains  of  the  umbilical  arteries,  and  run  up  from 
the  sides  of  the  bladder.  The  ligamentum  inferius 
vesicas  connects  the  bladder  to  the  upper  and  inner 
side  of  the  ossa  pubis. 

Observe  the  parts  of  the  bladder  not  covered  by 
peritoneum;  as  they  are  the  situations  of  surgical 
operations.  These  are  the  whole  anterior  surface, 
lying  against  the  pubis,  and  rising  above  it,  when  the 

*  la  the  foetus,  it  is  a  prolongation  or  production  of  the  coats  of  the 
bladder. 


58  LONDON    DISSECTOR,  OR 

bladder  is  distended,  so  that  it  may  be  punctured 
above  the  pubis; — the  sides,  at  the  very  lowest  part  of 
which  the  incision  is  made  in  the  lateral  operation  of 
lithotomy,  and  where  the  viscus  may  be  punctured 
from  the  perineum; — and  the  inferior  surface,  resting 
on  the  rectum,  and  allowing  us  to  puncture  from  it. 
Observe  also  the  direction  of  the  axis  of  the  bladder, 
in  conformity  with  which  all  instruments  should  be 
introduced. 

10.  The  entrance  of  the  ureters  into  the  bladder  on 
the  outside  of  the  vesiculas  seminales. 

11.  The  rectum,  following  the  curve  of  the  os 
sacrum,  and  os  coccygis. 

12.  The  prepuce  is  a  fold  of  skin  forming  a  sheath 
or  covering  for  the  glans  penis.     It  makes  a  duplica- 
ture  extending  along  the  flat  part  of  the  glans  from  its 
basis  to  the  orifice  of  the  urethra,  termed  FR^NUM 
PR^PUTII. 

To  have  a  more  connected  view  of  the  relative 
situation  of  these  important  parts,  one  side  of  the 
pelvis  should  now  be  removed,  by  dividing  the  sym- 
physis  pubis,  and  by  sawing  through  the  os  ileum,  or 
separating  it  at  its  junction  with  the  sacrum.  By 
carefully  removing  all  the  cellular  membrane,  the 
student  will  be  enabled  more  accurately  to  examine 
the  situation  of  the  parts  above  described. 

OF   THE    SCROTUM. 

The  scrotum  consists  externally  of  a  loose,  rugose 
skin,  and  internally  of  condensed  cellular  membrane, 
which  has  been  described  as  a  muscle,  under  the 
name  of  Dartos. 

On  dividing  the  anterior  part  of  the  scrotum,  on 
either  side  of  the  raphe,  we  expose, 

1,  The  Testicle,  a  gland  of  an  oval  flattened  form, 


GUIDE   TO    ANATOMY.  59 

covered  by  the  tunica  vaginalis,  having  on  its  upper 
edge  an  appendage  termed  Epididymis. 

I.  The  Spermatic  Chord,  connecting  the  testicle 
to  the  abdominal  ring.  It  consists  of, 

#,  The  spermatic  artery,  a  branch  of  the  aorta; 
this  divides  into  several  branches,  which  enter  the 
upper  edge  of  the  testicle. 

6,  The  spermatic  veins,  which  form  a  plexus,  that 
terminates  in  the  abdomen,  in  a  single  vein. 

c,  The  spermatic  nerves,  which  come  from  the 
intercostal  and  lumbar  nerves. 

d,  The  vas  deferens,  or  excretory  duct  of  the  tes- 
ticle;— this  is  situated  in  the  back  part  of  the  chord, 
and  is  distinguished  by  its  firm  cartilaginous  feel. 

e,  The  spermatic  absorbents. 

/,  These  parts  are  all  connected  by  cellular  mem- 
brane, and  by  the  tunica  vaginalis,  which  is  covered 
by  a  thin  muscle. 

g,  The  cremaster; — this  arises  from  the  obltquus 
descendens  internus,  and  is  lost  on  the  tunica  vaginalis. 

The  internal  proper  covering  of  the  testicle  is  a 
serous  coat,  and  is  denominated  the  tunica  albuginea. 


CHAPTER    III. 

DISSECTION  OF  THE  ORGANS  OF  GE- 
NERATION  IN  THE   FEMALE. 

PREVIOUS  to  the  dissection,  it  will  be  proper  to 
examine  the  external  parts. 

The  MONS  VENERIS  is  a  rounded  prominence, 
covered  with  hairs  after  puberty,  situated  at  the 
lower  part  of  the  belly,  and  arising  on  each  side 
gradually  from  the  groins;  it  consists  of  the  common 


60  LONDON   DISSECTOR,  OR 

integuments,  with  an  additional  quantity  of  cellular 
and  adipose  substance,  and  lies  upon  the  fore  part  of 
the  ossa  pubis.  From  the  inferior  part  of  the  mons 
veneris  arise 

The  LABI  A  EXTERN  A,  called  also  the  labia  or  alae 
pudendi: — they  are  continued  downwards  and  forwards 
in  the  direction  of  the  symphysis  pubis,  and  terminate 
in  the  perineum  anterius:  they  consist  of  integuments, 
cellular  substance,  and  fat, — are  thicker  above  than 
below, — and  are  red  and  vascular  on  their  inner  side. 
The  places  where  the  labia  are  joined  to  each  other 
above  and  below,  are  termed  Commissures. 

The  longitudinal  cavity  or  fissure,  situated  betwixt 
the  labia,  and  extending  from  the  mons  veneris  to  the 
perineum  anterius,  is  sometimes  called  the  SINUS 
PUDORIS;  it  is  broader  above  than  below,  and  contains 
several  other  parts. 

On  separating  the  labia,  we  see,  immediately  below 
the  superior  commissure, 

The  CLITORIS,  a  red  projecting  body,  situated  be- 
low the  arch  of  the  pubis,  and  partly  covered  by  its 
PREPUCE:  The  prepuce  is  a  fold  of  skin,  continued 
from  the  inner  surface  of  the  labia,  so  as  to  cover  the 
superior  and  lateral  parts  of  the  clitoris. — The  clitoris 
resembles  the  penis  of  the  male,  and  consists  of  two 
cavernous  bodies;  these  cannot,  however,  be  traced  in 
this  stage  of  the  dissection.  That  part  of  the  body 
which  forms  an  obtuse  projection  externally,  is  called 
the  GLANS. 

The  PERINEUM  ANTERIUS  is  that  portion  of  the  soft 
parts  which  extends  from  the  inferior  commissure  of 
the  labia  to  the  anus. 

The  PERINEUM  POSTERIUS  is  the  space  betwixt  the 
anus  and  point  of  the  os  coccygis. 

The  NYMPHS  are  two  prominent  doublings  of  the 
integuments,  extending  from  the  glans  of  the  clitoris  to 
the  sides  of  the  vagina.  Their  external  side  is  con- 


GUIDE   TO    ANATOMY.  61 

tinued  from  the  inner  surface  of  the  labia,  and  from 
the  prepuce  of  the  clitoris,  while  their  internal  surface 
seems  immediately  continued  from  the  fine,  thin,  vas- 
cular integuments  covering  the  clitoris  itself;  they  are 
spongy,  and  consist  internally  of  cellular  and  adipose 
substance. 

A  little  lower  we  see  the  orifice  of  the  urethra;  it  is 
situated  below  the  clitoris  and  arch  of  the  pubis,  be- 
twixt the  nymphae,  and  above  the  orifice  of  the  vagina: 
it  consists  of  a  small  rising  prominence  like  a  pea,  in 
the  centre  of  which  is  a  small  opening  or  hole. 

On  each  side  of  the  orifice  of  the  urethra,  we  meet 
generally  with  the  orifices  of  two  mucous  glands,  which 
by  some  are  named  COWPER'S  GLANDS  of  the  female. 

On  separating  the  lower  part  of  the  labia  pudendi, 
we  see  the  VESTIBULUM,  a  space  which  leads  to  the 
vagina;  it  is  bounded  behind,  by  the  carunculas  myrti- 
formes,  or  by  the  hymen  in  virgins;  on  the  sides,  by 
the  labia;  before,  by  the  perineum  anterius,  which  pro 
jects  forwards,  forming  a  kind  of  valve,  so  that  a  little 
pit  is  formed  behind  it,  which  is  termed  Fossa  Navi- 
cularis,  or  Scaphoides. 

The  HYMEN,  or  Circulus  Membranosus,  is  a  thin 
and  extensile  membrane,  formed  by  a  doubling  of  the 
inner  surface  of  the  vestibulum  and  lower  part  of  the 
vagina,  the  entrance  of  which  is  by  its  means  much 
contracted  in  virgins.  It  generally  has  an  opening  in 
its  upper  part,  but  it  is  completely  ruptured  in  the  first 
coitus:  its  form  is  various,  frequently  semilunar,  and 
then  its  base  is  attached  to  the  vestibulum,  while  its 
cornua  extend  upwards  as  far  as  the  sides  of  the 
urethra. 

After  the  destruction  of  the  hymen,  in  married 

women,  we  see  some  irregular  projections  marking 

the  orifice  of  the  vagina,  and  termed  CARUNCUL.E 

MYRTIFORMES:   they  are  generally  supposed  to  be 

6 


the  remains  of  the  hymen,  but  are  not  exactly  in  the 
same  situation. 

Behind  these  is  the  VAGINA,  or  canal  leading  to  the 
uterus;  at  the  extremity  of  which  may  be  felt  project- 
ing the  Os  INTERNUM  UTERI,  or  Os  TINGLE,  but  it 
cannot  be  seen  without  dissection. 

The  skin  should  now  be  divided  on  the  side  of  the 
right  labium,  and  the  dissection  should  be  carried  from 
the  groin  to  the  side  of  the  anus;  the  cellular  membrane 
must  be  carefully  removed,  in  order  to  expose  the 
following  parts. 

We  find  the  CLITORIS  consisting  of  two  spongy 
bodies  termed  Crura,  which  unite  and  form  the  body. 
The  crus  of  each  side  is  a  cavernous  body,  arising 
from  the  ramus  and  upper  part  of  the  tuberosity  of  the 
ischium,  continued  along  the  ramus  of  the  os  pubis, 
and  uniting  with  its  fellow  opposite  to  the  symphysis 
pubis.  The  body  formed  by  the  crura  does  not  extend 
upwards,  but  forms  a  curve  downwards  towards  the 
urethra;  it  is  divided  internally  by  the  SEPTUM  PEC- 
TINIFORME,  and  is  attached  to  the  spmphysis  pubis  by 
a  suspensory  ligament:  it  is  invested  by  a  ligamentous 
membrane. 

The  muscles  which  are  met  with  in  this  dissection 
consist  of  four  pair,  and  two  single  muscles. 

The  ERECTOR  CLITORIDIS,     1 
TRAWVERSUS  PEKING,  I 
LEVATOR  ANI, 
COCCYGEUS,  J 

The  SPHINCTER  Am,         j         A    ,  }es 

SPHINCTER  VAGINJE,  3 

1.  The  ERECTOR  CLITORIDIS  arises,  fleshy  and 
tendinous,  from  the  tuber  ischii,  from  the  inside  of  the 
ramus  of  the  os  ischium,  and  from  the  ramus  of  the  os 
pubis:  It  passes  over  the  crus  of  the  clitoris,  and  be- 
coming tendinous,  is  lost  upon  it. 


GUIDE    TO    ANATOMY.  63 

Arising  from  the  same  point,  and  surrounded  by 
much  cellular  membrane,  we  find, 

2.  The  TRANS  VERSUS  PERIN^I. — Its  origin  is  the 
same  as  in  the  male. 

It  is  inserted  into  a  ligamentous  substance  in  the  pe- 
rineum antenus,  at  the  point  where  the  sphincter  ani 
and  sphincter  vaginae  meet. 

This  ligamentous  or  tendinous  substance  deserves 
attention.  Here,  as  in  the  male,  it  is  the  point  of  union 
into  which  different  muscles  are  inserted. 

This  muscle  serves  to  sustain  the  perineum. 
.  3.  Surrounding  the  extremity  of  the  vagina,  and  a 
small  part  of  the  vestibulum,  we  find  the  SPHINCTER^ 
VAGINA;  it  arises  anteriorly,  from  the  crura  of  the  cli- 
toris on  each  side;  it  surrounds  the  orifice  of  the  vagi- 
na, and  is 

Inserted  into  the  ligamentous  point  of  the  perineum, 
where  the  fibres  of  each  side  meet,  and  are  connected 
with  those  of  the  transversi  perinaei,  and  with  the 
sphincter  ani. 

It  contracts  the  mouth  of  the  vagina,  and  compresses 
the  plexus  retiformis. 

4.  The  SPHINCTER  ANI  exactly  resembles  the  same 
muscle  in  the  male. 

5.  The  LEVATOR  ANI  resembles  the  same  muscle 
of  the  male;  it  surrounds  the  sides  of  the  vagina  in  part, 
and  consequently  assists  in  constricting  and  supporting 
it. 

6.  The  COCCYGEUS  is  longer  than  in  the  male,  from 
the  greater  transverse  diameter  of  the  inferior  aperture 
of  the  pelvis. 

Under  the  fibres  of  the  sphincter  vaginae,  you  will 
find  the  PLEXUS  RETIFORMIS,  or  CORPUS  CAVERNO- 
SUM  VAGIN2E,  a  spongy  body,  consisting  of  cellular 
substance,  interwoven  with  a  number  of  convoluted 
blood-vessels;  it  arises  from  the  sides  of  the  clitoris, 
passes  on  each  side  of  the  extremity  of  the  vagina,  is 


64  LONDON    DISSECTOR,  OR 

not  continued  completely  around  it,  but  is  lost  on  its 
posterior  part. 

The  VAGINA  is  the  canal  leading  from  the  vestibu- 
lum  to  the  uterus.  It  lies  betwixt  the  rectum  and 
inferior  surface  of  the  urethra  and  bladder,  and  is 
connected  to  them  by  cellular  membrane.  It  is  com- 
posed of  fibrous  substance,  partly  ligamentous,  and 
perhaps  in  part  muscular;  its  inner  surface  is  rugose, 
vascular,  and  occupied  by  mucous  glands.  On  slitting 
it  up,  we  see,  at  its  posterior  extremity,  the  Os  Uteri, 
a  rounded  projection,  with  a  transverse  fissure. 

The  UTERUS,  or  WOMB. — This  organ  is  best  seen 
from  the  cavity  of  the  abdomen.  It  is  situated  betwixt 
the  bladder  and  rectum,  to  both  of  which  it  is  con- 
nected by  reflections  of  peritoneum;  it  is  of  the  shape 
of  a  pear,  somewhat  flattened,  inwardly  hollow,  out- 
wardly of  a  whitish  color,  and  of  a  firm  consistence. 
The  broad  upper  part  of  the  womb  is  called  the  Fun- 
dus  Uteri,  the  narrower  part  is  named  the  neck,  or 
Cervix  Uteri,  and  the  intermediate  part  its  Body. 

The  uterus  has  four  ligaments,  two  on  each  side: 

1.  The  LIGAMENTUM  TERES,  or  Round  Ligament. 
It  is  a  round  long  cord,  extending  from  the  side  of  the 
fundus  uteri,  and  passing  through  the  abdominal  ring, 
to  be  lost  in  the  groin. 

The  LIGAMENTUM  LATUM,  or  Broad  Ligament,  is 
a  broad  fold  of  peritoneum,  reflected  from  the  body  of 
the  uterus,  and  connecting  it  on  the  sides  of  the  pelvis. 
The  uterus,  together  with  its  two  broad  ligaments, 
divides  the  pelvis  into  an  anterior  and  posterior  half; 
in  the  former  of  which  is  the  bladder,  and  in  the  latter 
the  rectum.  The  duplicature  of  the  broad  ligament 
encloses  the  Fallopian  tube,  ovary,  and  round  liga- 
ment. 

The  FALLOPIAN  TUBES  are  two.  Each  tube  is  con- 
tained in  the  upper  part  of  the  doubling  of  the  broad 
ligament;  it  goes  out  from  the  fundus  of  the  womb,  and 


GUIDE    TO    ANATOMY.  65 

is  a  slender  hollow  tube:  its  outer  end  is  curved  down- 
wards and  backwards,  and  terminates  by  a  broad 
fringed  extremity,  termed  MORSUS  DIABOLI,  or  the 
FIMBRLE.  This  broad  extremity  is  connected  to  the 
next  pair  of  organs. 

The  OVARIA  are  two  small  oval  bodies,  white  and 
flat,  situated  by  the  sides  of  the  uterus,  and  inclosed 
in  the  posterior  fold  of  the  broad  ligament  behind  the 
Fallopian  tube;  each  ovarium  is  connected  to  the  fun- 
dus  uteri  by  a  short  and  round  ligament. 

The  BLADDER  is  situated  before  the  uterus,  and  is 
described  in  the  preceding  chapter. 

The  URETHRA  is  short  in  females,  and  near  the 
bladder  is  surrounded  by  a  spongy  fleshy  substance, 
is  connected  to  the  cartilaginous  arch  of  the  pubis  by 
the  ligamentum  inferius  vesicae. 

The  URETER  descends  from  the  kidneys  over  the 
psoas  muscle;  it  runs  for  some  space  betwixt  the  blad- 
der and  vagina,  and  at  last  perforates  the  bladder  near 
the  neck. 

The  RECTUM  lies  behind  the  uterus.  See  the  pre- 
ceding chapter. 

To  obtain  a  more  satisfactory  knowledge  of  the 
relative  situation  of  the  parts,  the  left  side  of  the  pelvis 
should  be  removed  as  in  the  male,  and  the,  parts  exam* 
ined  in  that  situation. 


CHAPTER.   IV. 
DISSECTION   OF   THE   THIGH 


SECTION.    I. 
OF  THE  ANTERIOR  PART  OF  THE  THIGH. 

Of  the  Fascia^  cutaneous  vessels^  and  nerves. 

BENEATH  the  integuments,  you  will  find  a  strong 
fascia,  or  aponeurotic  expansion,  investing  the  whole 
thigh,  called  the  FASCIA  LATA  FEMORIS.  It  consists 
partly  of  tendinous,  partly  of  ligamentous  fibres;  sur- 
rounds and  covers  all  the  muscles,  and  sends  septa  or 
partitions  between  them: — It  is  very  strong,  smooth, 
and  tendinous  on  the  outer  part  of  the  thigh;  but,  on 
the  anterior  and  inner  part,  it  is  very  thin,  and  of  a 
cellular  texture.  Consequently  to  demonstrate  the 
whole  extent  of  this  fascia,  it  should  be  first  exposed 
on  the  outside  of  the  thigh,  and  the  dissection  continued 
carefully  inwards  on  the  fore-part,  where  it  is  with 
difficulty  distinguished  from  the  common  cellular  mem- 
brane. 

But,  in  removing  the  common  integuments  from  the 
fore  part  of  the  thigh,  it  will  be  proper  to  attend  to 
some  parts  which  are  situated  above  the  fascia. 

1 .  The  VENA  SAPHENA  MAJOR  is  seen  running  up 
on  the  inside  of  the  knee  and  thigh.  At  first  it  lies 
very  superficial,  betwixt  the  skin  and  fascia.  As  it 
ascends,  it  is  gradually  enveloped  by  the  fibres  of  the 
fascia,  and  then  sinks  beneath  it  to  join  the  femoral 


GUIDE    TO    ANATOMY.  67 

vein  about  an  inch  below  Poupart's  ligament,  receiv- 
ing in  its  course,  several  cutaneous  veins. 

2.  Immediately   under   the  true   skin,   and   more 
superficial  than  the  veins  or  nerves,  you  may  occa- 
sionally perceive  the  LYMPHATIC  VESSELS  running, 
like  lines  of  a  whitish  colour,  to  enter  the  inguinal 
glands:  they  are  more  numerous  on  the  fore  part,  than 
on  the  outside  of  the  thigh. 

3.  Several  CUTANEOUS  NERVES  proceeding  from 
the  lumbar  or  anterior  crural  nerve,  are  seen  ramifying 
above  the  fascia. 

The  fascia  may  now  be  exposed  distinctly.  Observe 
how  extensively  it  arises  from  the  bones,  tendons, 
and  ligaments.  On  the  anterior  and  superior  part 
of  the  thigh,  it  arises  from  Poupart's  ligament,*  from 
the  os  pubis,  the  descending  ramus  of  that  bone,  and 
the  ascending  ramus  and  tuberosity  of  the  ischium;  — 
behind,  and  on  the  outside,  from  the  whole  spine  of 
the  ilium,  and  from  the  sacro-sciatic  ligaments.  It 
receives  a  number  of  fibres  from  a  muscle  belonging 
to  it,  viz.:  the  tensor  vaginae  femoris,  and  from  the 
tendon  of  the  gluteus  maximus;  —  passing  down  over 
the  whole  thigh,  it  is  firmly  fixed  to  the  linea  aspera, 
the  condyles  of  the  femur,  and  the  patella,  and  is  con- 
tinued over  the  knee,  to  IDC  attached  to  the  heads  of 
the  tibia  and  fibula,  and  form  the  fascia  of  the  leg. 

On  the  upper  and  anterior  part  of  the  thigh,  there 
is  a  slight  hollow,  where  the  great  vessels  descend 
under  the  crural  arch.  The  fascia  lata  forms  just  on 
the  outside  and  upper  part  of  this,  a  crescent-shaped 
fold,  called  its  semilunar  edge,  which  is  strongly  con- 
nected to  the  crural  arch,  and  sometimes  contributes 
to  the  strangulation  in  femoral  hernia. 


*  At  this  part  the  fascia  of  the  thigh  is  covered  by  a  more  superficial 
expansion,  which  lies  over  the  lower  part  of  the  aponeurosis  of  the  ex- 
ternal oblique  muscle,  completely  covers  the  crural  arch,  and  descends 
some  little  way  beyond  the  bend  of  the  thigh.  It  has  been  called  the 
superficial  fascia. 


68  LONDON    DISSECTOR,  OR 

The  fascia  should  now  be  dissected  back;  and,  in 
lifting  up  the  thicker  part  of  it,  which  covers  the 
outside  of  the  thigh,  you  may  observe  that  it  is  com- 
posed of  two  laminae  of  fibres,  the  fibres  of  the  outer 
lamina  run  in  circles  round  the  thigh,  while  those  on 
the  inner,  stronger,  and  more  firmly  connected,  run 
longitudinally. 

The  muscles  on  the  anterior  part  of  the  thigh 
are  nine  in  number. 

1.  The  TENSOR  VAGINAE  FEMORIS — Jlrises,  by  a 
narrow,  tendinous,  and  fleshy  origin,  from  the  external 
part  of  the  anterior  superior  spinous  process  of  the  os 
ilium:  it  forms  a  considerable  fleshy  belly,  and  ex- 
tending downwards  and  backwards,  is 

Inserted  into  the  inner  lamina  of  the  great  fascia, 
where  it  covers  the  outside  of  the  thigh,  and  a  little 
below  the  trochanter  major. 

This  muscle,  called  also  the  Fascialis,  serves  to 
stretch  the  great  fascia  of  the  thigh,  to  assist  in  the 
abduction  of  the  thigh,  and  in  its  rotation  inwards. 

2.  THE   SARTORIUS — Arises,   by  short   tendinous 
fibres,  from  the  anterior  superior  spinous  process  of 
the  os  ilium,  soon  becomes  fleshy,  extends  obliquely 
across  the  thigh,  and  passes  behind  the  inner  condyle. 

Inserted,  by  a  broad  and  thin  tendon,  into  the  inner 
side  of  the  tibia,  immediately  below  its  anterior 
tubercle. 

This  muscle  lies  before  the  muscles  of  the  thigh, 
crossing  them  like  a  strap  about  two  inches  in  breadth, 
and  serves  to  flex  the  leg  obliquely  inwards  on  the 
thigh,  and  to  bend  the  thigh  forwards. 

3.  The  RECTUS   FEMORIS — Arises,   by   a    strong 
tendon,  from  the  inferior  anterior  spinous  process  of 
the  os  ilium;  and,  by  another  strong  tendon,  from 
the  dorsumof  that  bone  a  little  above  the  acetabulum, 
and  from  the  capsular  ligament  of  the  hip-joint.     The 
two  tendons  soon  unite,  and  send  off  a  large  belly, 


GUIDE    TO    ANATOMY.  69 

which  runs  down  over  the  anterior  part  of  the  thigh, 
forming  a  complete  peniform  muscle,  and  terminates 
in  a  flat  but  strong  tendon,  which  is 

Inserted  into  the  upper  extremity  of  the  patella; 
where  a  thin  aponeurosis  is  sent  from  it  over  the  fore 
part  of  that  bone,  to  terminate  on  the  strong  ligament 
which  connects  the  lower  part  of  the  patella  to  the 
tibia,  and  is  called  Ligamentum  Patellae. 

[t  serves  to  extend  the  leg  on  the  thigh,  to  bend 
the  thigh  on  the  pelvis,  and  to  bring  the  pelvis  and 
thigh  forwards  on  the  leg. 

Under  the  rectus,  and  partly  covered  by  it,  there  is 
a  large  mass  of  flesh,  which,  at  first  sight,  appears  to 
form  but  one  muscle.  It  may,  however,  be  divided 
into  three;  the  separation  on  the  external  surface  is 
not  generally  very  evident,  but,  by  following  the 
course  of  the  vessels  which  enter  -this  mass,  and  by 
cutting  through  perhaps  a  few  fibres  externally,  you 
will  discover  the  line  of  separation,  and  this  separa- 
tion, as  you  proceed  deeper  with  your  dissection, 
will  become  very  distinct.  The  three  muscles  are 
named  vastus  externus,  vastus  internus,  and  crurseus: 
at  the  upper  and  middle  parts  of  the  thigh,  they  may 
be  separated  very  distinctly;  but  for  two  or  three  inches 
above  the  condyles,  they  are  inseparably  connected. 

4.  The  VASTUS  EXTERNUS — Jlrises.,  tendinous  and 
fleshy,  from  the  anterior  surface  of  the  root  of  the 
trochanter  major,  from  the  outer  edge  of  the  linea 
aspera,  its  whole  length, — from  the  oblique  line  run- 
ning to  the  external  condyle, — and  from  the  whole 
external  flat  surface  of  the  thigh  bone.  The  fleshy 
fibres  run  obliquely  forwards. 

Inserted  into  the  external  surface  of  the  tendon  of 
the  rectus  cruris,  and  into  the  side  of  the  patella: — 
Part  of  its  ends  likewise  in  an  aponeurosis  which 
passes  over  the  side  of  the  knee  to  the  leg,  and  is 


70  LONDON    DISSECTOR,  OR 

firmly  fixed  to  the  head  of  the  tibia,  closely  adhering 
to  the  capsule  of  the  knee-joint. 

It  extends  the  leg,  or  brings  the  thigh  forward  upon 
the  leg. 

5.  The  VASTUS  INTERNUS — Arises,  tendinous  and 
fleshy,  from  the  fore-part  of  the  root  of  the  trochanter 
minor,  from  all  the  upper  edge  of  the  linea  aspera 
from  the  oblique  line  running  to  the  inner  condyle, 
and  from  the  whole  internal  surface  of  the  thigh  bone. 
Its  fibres  descend  obliquely  downwards  and  forwards. 

Inserted  into  the  lateral  surface  of  the  tendon  of  the 
rectus  cruris,  and  into  the  side  of  the  patella;  it  also 
sends  off  an  aponeurosis,  which  is  continued  down  to 
the  leg,  and  covers  the  inner  part  of  the  capsule  of 
the  knee. 

6.  The   CRUR^US,  or  CRULALIS. — The  principal 
part  of  this  muscle  is  lapped  over,  and  concealed,  by 
the  bellies  of  the  two  vasti;  and  the  small  part,  which 
is  seen  projecting  between  the  anterior  edges  of  those 
muscles,  lies  behind  the  belly  of  the  rectus  cruris. 

Arises ,  fleshy,  from  between  the  two  trochanters  of 
the  os  femoris,  from  all  the  fore-part  of  the  bone,  and 
from  the  outside  as  far  back  as  the  linea  aspera;  but 
from  the  inside  of  the  bone  it  does  not  arise,  for  be- 
tween the  forepart  of  the  femur  and  the  inner  edge  of 
the  linea  aspera,  there  is  a  smooth  plain  surface,  of  the 
breadth  of  an  inch,  extending  nearly  the  whole  length 
of  the  bone,  from  which  no  muscular  fibres  arise. 

Inserted  into  the  posterior  surface  of  the  tendon  of 
the  rectus,  and  the  upper  edge  of  the  patella. 

7.  The  GRACILIS  arises,  by  a  broad  thin  tendon, 
from  the  lower  half  of  that  part  of  the  os  pubis  which 
forms  the  symphysis,  and  from  the  inner  edge  of  the 
descending  ramus: — It  soon  grows  fleshy,  and  forms  a 
belly,  which  becoming  narrower  as  it  descends,  termi- 
nates in  a  tendon,  which  passes  behind  the  inner  con- 


GUIDE    TO    ANATOMY.          N  71 

dyle  of  the  thigh  bone,  and  is  reflected  forwards,  to 
be 

Inserted  in  the  inside  of  the  tibia  below  the  tendon 
of  the  sartorius,  and  above  that  of  the  semitendinosus. 

It  serves  to  bring  the  thigh  inwards  and  forwards, 
and  assists  in  bending  the  leg. 

8.  The  PECTINALIS — Arises,  fleshy  from  that  ridge 
of  the  os  pubis  which  forms  the  brim  of  the  pelvis,  and 
from  the  concave  surface  below  the  ridge.     It  forms 
a  thick  flat  belly, 

Inserted,  by  a  flat  tendon  into  the  linea  aspera,  im- 
mediately below  the  less  trochanter. 

Its  origin  lies  on  the  inside  of  the  belly  of  the  psoas 
magnus,  where  that  muscle  slides  over  the  brim  of  the 
pelvis,  and  on  the  outside  of  the  origin  of  the  adductor 
longus.  It  bends  the  thigh  forwards,  moves  it  inwards, 
and  performs  rotation,  by  turning  the  toes  outwards. 

9.  The  TRICEPS  ADDUCTOR  FEMORIS  consists  of 
three  distinct  muscles,  which,  passing  from  the  pelvis 
to  the  thigh,  lie  in  different  layers  upon  one  another, 
and  have  nearly  the  same  action. 

(1.)  The  ADDUCTOR  LONGUS,  or  PRIMUS — Arises, 
by  a  short  strong  tendon,  from  the  upper  and  fore  part 
of  the  os  pubis,  near  its  symphysis; — forms  a  large 
triangular  belly,  which,  as  it  descends,  becomes  broad- 
er, but  less  thick. 

Inserted,  tendinous,  into  the  middle  part  of  the  linea 
aspera,  occupying  rather  more  than  one-third  of  its 
length. 

(2.)  The  ADDUCTOR  BREVIS,  or  SECUNDUS — Ari- 
ses, fleshy  and  tendinous,  from  the  os  pubis,  between 
the  lower  part  of  the  symphysis  pubis,  and  the  fora- 
men thyroideum: — it  forms  a  fleshy  belly, 

Inserted,  tendinous,  into  the  upper  third  of  the  linea 
aspera,  that  is,  from  the  root  of  the  less  trochanter  to 
the  commencement  of  the  insertion  of  the  next  muscle. 


72  LONDON    DISSECTOR,  OR 

(3.)  The  ADDUCTOR  MAGNUS,OF  TERTIUS. — «#mes, 
principally  fleshy,  from  the  lower  part  of  the  body  and 
the  descending  ramus  of  the  os  pubis,  arid  from  the  as- 
cending ramus  of  the  ischium,  as  far  as  the  tuberosity 
of  that  bone.  The  fibres  run  outwards  and  down- 
wards, having  various  degrees  of  obliquity. 

Inserted,  fleshy,  into  the  whole  length  of  the  linea 
aspera,  into  the  oblique  ridge  above  the  internal  con- 
dyle  of  the  osfemoris,  and,  by  a  roundish  long  tendon, 
into  the  upper  part  of  that  condyle. 

This  large  muscle  arises  behind  and  below  the  two 
other  adductors;  it  forms  a  flat  partition  betwixt  the 
muscles  on  the  fore  and  back  parts  of  the  thigh. 

All  these  muscles  serve  to  approximate  the  thighs 
to  each  other,  and  to  roll  them  outwards.  The  two 
anterior  heads  will  bend  the  thigh;  the  posterior  will 
extend  it,  if  it  be  bent  forwards. 


SECTION     II. 

OF   THE    POSTERIOR    PART    OF   THE    THIGH. 

\ 

Of  the  fascia. 

ABOVE  that  part  of  the  great  fascia  which  invests 
the  thigh  posteriorly,  we  meet  with  several  cutaneous 
nerves.  They  are  of  little  importance,  taking  their 
origin  either  from  the  lumbar  nerves,  and  passing  over 
the  spine  of  the  os  ilium,  or  from  the  great  sciatic 
nerve,  and  emerging  from  the  lower  margin  of  the 
gluteus  maximus.  Other  twigs  come  from  the  sacral 
nerves,  and  from  the  sciatic  in  its  course  down  the 
thigh. 

The  muscles  situated  on  the  posterior  part  of  the 
thigh  are  eleven. 


GUIDE    TO    ANATOMY.  73 

On  removing  the  integuments  and  fascia  from  the 
hip,  we  expose 

1 .  The  GLUTEUS  MAXIMUS. — It  arises,  fleshy,  from 
the  posterior  third  of  the  spine  of  the  os  ilium,  from 
the  whole  lateral  surface  of  the  sacrum,  below  the 
posterior  spinous  process  of  the  ilium;  from  the  back 
part  of  the  posterior  or  inferior  sacro-sciatic  liga- 
ment,* over  which  the  edge  of  this  muscle  hangs  in  a 
folded  manner,  and  from  the  lateral  surface  of  the  os 
coccygis. 

The  fleshy  fibres  proceed  obliquely  forwards  and 
downwards,  forming  a  thick  broad  coarse  muscle,  and 
converging  gradually,  terminate  in  a  strong  flat  tendon. 
This  tendon  slides  over  the  posterior  part  of  the 
trochanter  major;  sends  off  a  great  quantity  of  tendi- 
nous fibres,  to  be  inseparably  joined  to  the  fascia  lata 
of  the  thigh;  and  is 

Inserted,  into  a  rough  surface  at  the  upper  and  outer 
part  of  the  linea  aspera,  immediately  below  the  tro- 
chanter major;  also  very  extensively  into  the  fascia 
lata,  which  covers  the  former  insertion. 

This  muscle  is  quite  superficial,  covering  all  the 
other  muscles  which  are  situated  on  the  back  part  of 
the  hip,  covering  also  the  tuber  ischii,  and  the  ten- 
dons of  the  muscles  which  arise  from  that  projection. 

It  is  used  to  restore  the  thigh,  after  it  has  been 
bent; — to  rotate  it  outwards;  to  extend  the  pelvis  on 
the  thigh,  and  maintain  it  in  that  position  in  the  erect 
posture  of  the  body. 

*  The  sacro-sciatic  ligaments  are  two  in  number;  they  pass  between 
the  ischium  and  sacrum. 

1.  The  external  or  inferior,  or  posterior,  sacro-seiatic  ligament  arises 
from  the  external  edge  of  the  transverse  processes  of  the  sacrum,  descends 
obliquely,  and  is  inserted  into  the  tuberosity  of  the  os  ischium. 

2.  The  internal,  or  anterior,  arises  from  the  edge  of  the  transverse 
processes  of  the  sacrum,  and  of  the  os  coccygis;  it  passes  across  on  the 
inside  of  the  external,  and  is  inserted  into  the  point  of  the  spinous  process 
of  the  ischium. 


74  LONDON    DISSECTOR,  OR 

By  raising  this  muscle  from  its  origin,  we  expose 

2.  The    GLUTEUS    MEDIUS — Arises,  fleshy,  from 
all  the  outer  edge  of  the  spine  of  the  os  ilium,  as  far 
as  the  posterior  tuberosity;  from  the  dorsum  of  the 
bone,   between  the    spine,    and    semicircular   ridge 
(which  passes  from  the  anterior  superior  spinous  pro- 
cess to  the  ischiatic  notch;)  also  from  the  rough  surface 
which  extends  from  the  anterior  superior  to  the  ante- 
rior inferior  spinous  process,  and  from  the  inside  of  a 
fascia  which  covers  its  anterior  part.     The  fibres  con- 
verge into  a  strong  and  broad  tendon,  which  is 

Inserted  into  the  upper  and  outer  part  of  the  great 
trochanter. 

The  posterior  part  of  the  belly,  and  the  tendon  of 
this  muscle,  are  concealed  by  the  gluteus  maximus, 
but  the  anterior  and  largest  part  is  superficial,  being 
covered  only  by  a  fascia. 

Having  lifted  up  this  muscle  from  its  origin,  you 
will  discover, 

3.  The  GLUTEUS   MINIMUS. — It  is  entirely  con- 
cealed by  the  gluteus  medius,  and  between  their  ten- 
dons there  is  a  bursa  mucosa. 

It-arises,  fleshy,  from  the  semicircular  ridge  of  the 
ilium,  and  from  the  dorsum  of  the  bone  below  the 
ridge  within  half  an  inch  of  the  acetabulum.  Its 
fibres  run  in  a  radiated  direction  towards  a  strong 
tendon, 'which  is 

Inserted  into  the  anterior  and  superior  part  of  the 
great  trochanter. 

4.  The  PYRIFORMIS — Arises^  within  the  pelvis,  by 
three  tendinous  and  fleshy  origins,  from  the  second, 
third,  and  fourth  false  vertebras  or  divisions  of  the 
sacrum.     It  forms  a  thick  belly,  which  passes  out  of 
the  pelvis,  below  the  niche  in  the  posterior  part  of 
the  ilium,  (from  which  it  receives  a  few  fleshy  fibres,) 
and  above  the  superior  sacro-sciatic  ligament. 


GUIDE    TO    ANATOMY.  75 

Inserted,  by  a  roundish  tendon,  into  the  uppermost 
part  of  the  cavity  at  the  root  of  the  trochanter  major. 

Like  the  other  small  muscles  of  the  hip,  it  is  entirely 
concealed  by  the  gluteus  maximus;  its  belly  lies  behind 
and  below  the  gluteus  medius,  but  is  not  at  all  covered 
by  it,  and  above  the  superior  gemellus.  Sometimes 
the  pyriformis  is  divided  into  two  distinct  muscles,  by 
a  branch  of  the  great  sciatic  nerve. 

It  moves  the  thigh  a  little  upwards,  and  rolls  it 
outwards. 

5.  The  GEMINI  consist  of  two  heads  which  are 
distinct  muscles. 

(1.)  The  superior  arises  from  the  back  part  of  the 
spinous  process  of  the  ischium. 

(2.)  The  inferior  from  the  upper  part  of  the  tube- 
rosity  of  the  os  ischium,  and  the  anterior  surface  of 
the  posterior  sacro-sciatic  ligament. 

Inserted^  tendinous  and  fleshy,  into  the  cavity  at  the 
root  of  the  trochanter  major,  immediately  below  the 
insertion  of  the  pyriformis,  and  above  the  insertion  of 
the  obturator  externus. 

They  lie  below  the  pyriformis,  and  above  the  quad- 
ratus  femoris;  they  are  united  by  a  tendinous  and 
fleshy  expansion,  which  forms  a  purse  or  sheath  for 
the  tendon  of  the  obturator  internus. 

They  serve  to  roll  the  thigh  outwards,  and  to  bind 
down  the  tendon  of  the  obturator  internus. 

Lying  between  the  bellies  of  the  gemini,  you  will 
perceive, 

6.  The  OBTURATOR  INTERNUS,  once  called  mar- 
supialis. — It  arises,  tendinous  and  fleshy,  from  more 
than  one-half  of  the  internal  circumference  of  the  fora- 
men thyroideum,  and  from  the  inner  surface  of  the 
ligament  which  fills  up  that  hole;  its  inside  is  covered 
by  a  portion  of  the  levator  ani;   it  forms  a  flattened 
tendon,  which  passes  out  of  the  pelvis  in  a  sinuosity 


76  LONDON    DISSECTOR,  OR 

betwixt  the  spinous  process  and  tuberosity  of  the 
ischium;  and,  becoming  rounder,  is 

Inserted  into  the  pit  at  the  root  of  the  trochanter 
major. 

Its  origin  lying  within  the  pelvis,  cannot  be  exposed 
till  the  contents  of  that  cavity  are  removed. 

7.  The  QUADRATUS  FEMORIS — Arises,  tendinous  and 
fleshy,  from  an  oblique  ridge,  which  descends  from 
the  inferior  edge  of  the  acetabulum  along  the  body  of 
the  ischium,  between  its  tuberosity  and  the  foramen 
thyroideum:  its  fibres  run  transversely,  to  be 

Inserted,  fleshy,  into  a  rough  ridge  on  the  back  part 
of  the  femur,  extending  from  the  root  of  the  greater 
trochanter  to  the  root  of  the  less. 

Situation:  It  is  concealed  by  the  gluteus  maximus, 
lies  below  the  inferior  head  of  the  gemini,  and  above 
the  superior  fibres  of  the  adductor  magnus;  its  origin 
is  in  contact  with  the  origin  of  the  hamstring  muscles. 

It  rolls  the  thigh  outwards. 

On  lifting  up  the  quadratus  femoris  from  its  origin, 
and  leaving  it  supended  by  its  insertion,  you  discover, 
running  in  the  same  direction,  the  strong  tendon  of, 

8.  The    OBTURATOR    EXTERNUS. — This   muscle 
arises,  fleshy,  from  almost  the  whole  circumference  of 
the  foramen  thyroideum,  and  from  the  external  surface 
of  the  obturator  ligament;   its  fibres  pass  outwards 
through  the  notch  placed  between  the  inferior  margin 
of  the  acetabulum  and  the  tuberosity  of  the  ischium, 
wind  around  the  cervix  of  the  os  femoris,  adhering  to 
the  capsular   ligament,  and  terminate  in  a  strong 
tendon,  which  is 

Inserted  into  the  lowermost  part  of  the  cavity,  at  the 
root  of  the  trochanter  major,  immediately  below  the 
insertion  of  the  inferior  head  of  the  gemini. 

This  muscle  cannot  be  distinctly  seen,  until  all  the 
muscles  which  run  from  the  pelvis  to  the  upper  part 


GUIDE    TO    ANATOMY.  77 

Of  the  thigh  are  removed,  both  on  the  fore  and  back 
part. 

It  rolls  the  thigh  bone  obliquely  outwards. 

9.  The  BICEPS  FLEXOR  CRURIS — Arises  by  two  dis- 
tinct heads;  the  first,  called  the  LONG  HEAD,  arises  in 
common  with  the  semitendinosus,  by  a  short  tendon, 
from  the  outer  part  of  the  tuberosity  of  the  ischium,  and, 
descending,  forms  a  thick  fleshy  belly.     The  second, 
termed   the    SHORT    HEAD,   arises,   tendinous    and 
fleshy,  from  the  linea  aspera,  immediately  below  the 
insertion  of  the  gluteus  maximus;  and  from  the  oblique 
ridge  running  to  the  outer  condyle,  where  it  is  con- 
nected with  the  fibres  of  the  vastus  externus.      The 
two  heads  unite  at  an  acute  angle,  a  little  above  the 
external  condyle,  and  terminate  in  a  strong  tendon 
which  is 

Inserted  into  a  rough  surface  on  the  outside  of  the 
head  of  the  fibula. 

The  biceps  cruris,  as  it  is  called,  bends  the  leg,  and 
particularly  by  means  of  its  short  head  twists  the  leg- 
outwards  in  the  bent  state  of  the  knee. 

10.  The   SEMITENDINOSUS — Arises,  tendinous,  in 
common  with  the  long  head  of  the  biceps,  from  the  tu- 
berosity of  the  ischium;  it  has  also  some  fleshy  fibres 
arising  from  that  projection  more  outwardly: — as  it  de- 
scends, it  arises,  for  two  or  three  inches,  fleshy,  from 
the  inside  of  the  tendon  of  the  biceps;  forms  a  thick 
belly,  and  terminates  at  the  distance  of  three  or  four 
inches  from  the  knee  in  a  long  round  tendon,  which  be- 
coming flat,  passes  behind  the  head  of  the  tibia,  and  is 
reflected  forwards,  to  be 

Inserted  into  the  anterior  angle  of  that  bone,  some 
little  way  below  its  tubercle,  and  below  the  tendon  of 
the  gracilis.  The  belly  of  this  muscle  is  intersected, 
about  its  middle,  by  a  narrow  trans  verse  tendinous  line. 

It  bends  the  leg'  backwards,  and  slightly  inwards. 


78  LONDON    DISSECTOR,  OR 

11.  The  SEMIMEMBRANOSUS — Arises,  by  a  strong 
round  tendon,  from  the  upper  and  outer  part  of  the  tu- 
berosity  of  the  ischium;  the  tendon,  soon  becoming- 
broader,  sends  off  obliquely  a  fleshy  belly;  this  muscle 
is  continued,  fleshy,  much  lower  down  than  that  last 
described.  The  fleshy  fibres  terminate  obliquely  in 
another  flat  tendon,  which  passes  behind  the  inner  con- 
dyle,  sends  off  a  thin  aponeurotic  expansion  under  the 
inner  head  of  the  gastrocnemius,  to  cover  the  posterior 
part  of  the  capsule  of  the  knee-joint,  and  to  be  affixed 
to  the  external  condyle:  the  tendon  then  becoming 
rounder,  is 

Inserted  into  the  inner  and  back  part  of  the  head  of 
the  tibia. 

This  is  a  semi-penniform  muscle;  and  serves  to  bend 
the  leg  backwards. 

The  last  two  muscles  properly  form  the  inner  ham- 
string; but  some  enumerate  among  the  tendons  of  the 
inner  hamstring,  the  sartorius  and  gracilis. 


CHAPTER.  V. 
DISSECTION  OF  THE  LEG  AND  FOOT. 

SECTION    I. 
OF    THE    FORE    PART    OF    THE    LEG  AND    FOOT. 

ON  dissecting  off  the  integuments  from  the  fore  part 
of  the  leg,  we  find  a  strong  fascia  continued  from  the 
thigh;  it  adheres  firmly  to  every  projecting  point  of 
bone,  to  the  head  and  spine  of  the  tibia,  and  to  the 
fibula;  it  grows  thinner  towards  the  lower  part  of  the 
leg;  but  where  it  passes  over  the  ankle,  it  again  be- 
comes very  strong  by  its  adhesions  to  the  outer  and 


GUIDE    TO    ANATOMY.  79 

inner  ankle,  and  forms  a  strong  ANNULAR  or  TRANS- 
VERSE LIGAMENT,  which  binds  down  the  tendons,  and 
is  evidently  but  a  thicker  and  stronger  part  of  the 
general  fascia  of  the  leg.  This  annular  ligament  seems 
to  consist  of  two  distinct  cross  bands,  which,  going 
from  the  point  of  the  outer  ankle  and  neighboring  part 
of  the  os  calcis,  are  fixed  to  the  malleolus  internus, 
and  to  the  inside  of  the  os  naviculare. 

Before  removing  the  fascia,  it  will  be  proper  to 
remark, 

1 .  The  vena  saphena  major,  running  upon  the  inside 
of  the  tibia,  and  accompanied  by  a  cutaneous  nerve, 
the  nervus  saphenus. 

2.  Several  cutaneous  nerves,  branching  on  the  outer 
and  fore-part  of  the  leg  and  foot,  and  derived  from  the 
nervus  peroneus. 

The  fascia  should  then  be  dissected  off;  and,  in 
doing  this,  remark,  that  it  is  firmly  attached  to  the 
bones,  and  also  to  the  bellies  of  the  muscles  at  the 
upper  part  of  the  leg,  so  that  their  surfaces  appear 
ragged,  where  the  fibres  are  separated  which  arose 
from  the  inside  of  the  fascia:  Remark  also,  that  it 
sends  down  processes  between  the  muscles;  these  are 
named  intermuscular  ligaments,  or  tendons;  they  give 
origin  to  the  fibres  of  all  the  muscles  betwixt  which 
they  pass,  connecting  them  together  inseparably,  so 
that  the  dissection  is  difficult,  and  has  a  rough  appear- 
ance. 

MUSCLES    SITUATED    ON    THE    FORE    PART    AND  OUT- 
SIDE   OF    THE    LEG. 

THESE  are  six  in  number. 

1.  The  TIBIALIS  ANTICUS — Jlrises,  principally 
fleshy,  from  the  exterior  surface  of  the  tibia,  from  its 
anterior  angle  or  spine,  and  from  nearly  half  of  the 
interosseous  ligament;  from  these  surfaces  it  continues 


80  LONDON    DISSECTOR,  OR 

to  arise  down  two-thirds  of  the  length  of  the  bone; 
also  from  the  inner  surface  of  the  fascia  of  the  leg, 
and  from  the  intermuscular  ligaments.  The  fleshy 
fibres  descend  obliquely,  and  terminate  in  a  strong 
tendon,  which  crosses  from  the  outside  to  the  fore-part 
of  the  tibia,  passes  through  a  distinct  ring  of  the 
annular  ligament  near  the  inner  ankle,  runs  over  the 
astragulus  and  os  naviculare,  and  is 

Inserted  into  the  upper  and  inner  part  of  the  os 
cuneiforme  internum,  and  the  base  of  the  metatarsal 
bone  supporting  the  great  toe. 

It  draws  the  foot  upwards  and  inwards;  or,  in  other 
words,  bends  the  ankle-joint. 

2.  EXTENSOR  LONGUS  DIGITORUM  PEDIS — Arises, 
tendinous  and  fleshy,  from  the  outer  part  of  the  head 
of  the  tibia;  from  the  head  of  the  fibula;  from  the 
anterior  angle  of  the  fibula  almost  its  whole  length; 
and  from  part  of  the  smooth  surface  between  the 
anterior  and  internal  angles;  from  a  small  part  of  the 
interosseous  ligament;  from  the  fascia  and  intermus- 
cular ligaments. 

Below  the  middle  of  the  leg,  it  splits  into  four  round 
tendons,  which  pass  under  the  annular  ligament, 
become  flattened,  and  are 

Inserted  into  the  root  of  the  first  phalanx  of  each  of 
the  four  small  toes,  and  expanded  over  the  upper  side 
of  the  toes  as  far  as  the  root  of  the  last  phalanx. 

This  muscle  also  runs  entirely  superficial;  it  lies 
between  the  tibialis  anticus  and  peroneous  longus, 
being  firmly  connected  to  them  by  intermuscular  liga- 
ments; but,  at  the  lower  part  of  the  leg,  it  is  separated 
from  the  tibialis  anticus  by  the  extensor  pollicis  lon- 
gus, and  from  the  peroneus  longus  by  the  peroneus 
brevis. 

It  extends  all  the  joints  of  the  four  small  toes;  and 
bends  the  ankle  joint. 


GUIDE    TO    ANATOMY.  81 

3.  PERONEUS  TERTIUS — Jlrises,  fleshy,  from  the 
anterior  angle  of  the  fibula,  and  from  part  of  the 
smooth   surface   between   the   anterior  and   internal 
angles,  extending  from  below  the  middle  of  the  bone 
downwards  to  near  its  inferior  extremity; — sends  its 
fleshy  fibres  forwards  to  a  tendon,  which  passes  under 
the  annular  ligament  in  the  same  sheath  as  the1  extensor 
digitorum  longus,  and  is 

Inserted  into  the  base  of  the  metatarsal  bone  that 
supports  the  little  toe. 

The  belly  of  this  muscle  is  inseparably  connected 
with  the  extensor  longus  digitorum,  and  is  properly 
its  outer  part;  it  lies  between  that  muscle  and  the 
peroneus  brevis.  The  tendon  runs  down  on  the  out- 
side of  that  tendon  of  the  extensor  longus  digitorum 
which  goes  to  the  little  toe.  The  whole  of  the  muscle 
is  superficial. 

4.  EXTENSOR  PROPRIUS  POLUCIS  PEDIS — Arises^ 
tendinous  and  fleshy,  from  part  of  the  smooth  surface 
between  the  anterior  and  internal  angles  of  the  fibula^ 
and  from  the  neighbouring  part  of  the  interosseous 
ligament,  extending  from  some  distance  below  the 
head  of  the  bone  to  near  its  inferior  extremity;  a  few 
fibres  also  arise  from  the  lower  part  of  the  tibia; 
the  fibres  pass  obliquely  downwards  and  forwards 
into  a  tendon,  which,  inclining  inwards,  passes  over 
the  fore-part  of  the  astragalus  and  os  naviculare,  and 
over  the  junction  of  the  os  cuneiforme  internum  and  os 
cuneiforme  medium,  to  be 

Inserted  into  the  base  of  the  first  and  of  the  second 
phalanges  of  the  great  toe. 

This  is  a  very  slender  muscle;  its  belly  is  concealed 
between  the  tibialis  anticus  and  extensor  digitorum 
longus,  and  cannot  be  seen  till  those  muscles  are 
separated  from  one  another; — the  tendon  is  superficial, 
running  between  the  tendons  of  those  two  muscles. 


82  LONDON    DISSECTOR,  OR 

It  serves  to  extend  the  great  toe;  and  to  bend  the 
ankle. 

The  PERONEUS  LONGUS — Arises,  tendinous  and 
fleshy,  from  the  fore-part  and  outside  of  the  head  of 
the  fibula,  and  from  the  adjacent  part  of  the  tibia, 
from  the  external  angle  of  the  fibula,  and  from  the 
smooth  surface  between  the  anterior  and  external 
angles  as  far  down  as  one-third  of  the  length  of  the 
bone  from  its  lower  extremity;  also  from  the  fascia 
of  the  leg  and  intermuscular  ligaments.  The  fibres 
run  obliquely  outwards  into  a  tendon,  which  passes 
behind  the  outer  ankle,  through  a  grove  in  the  lower 
extremity  of  the  fibula:  it  is  then  reflected  forwards 
through  a  superficial  fossa  in  the  outside  of  the  os 
calcis,  passes  over  a  projection,  runs  in  a  groove  in  the 
os  cuboides,  passes  over  the  muscles  in  the  sole  of  the 
foot,  and  is 

Inserted ,  tendinous  into  the  outside  of  the  base  of 
the  metatarsal  bone  that  sustains  the  great  toe,  and 
into  the  os  cuneiforme  internum. 

The  tendon  of  this  muscle  is  superficial  where  it 
crosses  the  outside  of  the  os  calcis,  but  in  the  sole  of 
the  foot  it  is  concealed  by  the  muscles  situated  there, 
and  will  be  seen  in  the  dissection  of  that  part. 

It  extends  the  ankle-joint,  and  turns  the  sole  of  the 
foot  outwards. 

6.  The  PERONEUS  BREVIS— .#mes,  fleshy  from 
the  outer  edge  of  the  anterior  angle  of  the  fibula,  and 
from  part  of  the  smooth  surface  behind  that  angle; 
beginning  about  one-third  down  the  bone,  and  con- 
tinuing its  adhesion  to  near  the  ankle;  from  the  fascia 
of  the  leg,  and  from  the  intermuscular  ligaments: — 
The  fibres  run  obliquely  towards  a  tendon,  which 
passes  through  the  groove  of  the  fibula  behind  the 
outer  ankle,  being  there  inclosed  in  the  same  ligament 
with  the  tendon  of  the  peroneus  longus,  then  through 
a  separate  groove  on  the  outside  of  the  os  calcis,  and  is 


GUIDE    TO    ANATOMY.  83 

Inserted  into  the  external  part  of  the  base  of  the 
metatarsal  hone  that  sustains  the  little  toe. 

This  muscle  arises  between  the  extensor  longus 
digitorum  and  peroneus  longus;  its  belly  is  overlapped, 
and  concealed  by  the  belly  of  the  peroneus  longus; 
but,  as  it  continues  fleshy  lower  down,  it  is  seen, 
above  the  ankle,  projecting  on  each  side  of  the  tendon 
of  that  muscle: — Below,  it  is  separated  from  the 
peroneus  tertius  by  that  projection  of  the  fibula  which 
forms  the  outer  ankle,  and  which  is  only  covered  by 
the  common  integuments. 

It  has  the  same  use  as  that  of  the  peroneus  longus. 

MUSCLES  ON  THE  UPPER  PART  OF  THE  FOOT. 

Only  one  muscle  is  found  in  this  situation. 

EXTENSOR  BREVIS  DIGITORUM  PEDIS — Arises, 
fleshy  and  tendinous,  from  the  anterior  and  upper 
part  of  the  os  calcis,  from  the  os  cuboid es,  and  from 
the  astragalus;  forms  a  fleshy  belly,  divisible  into  four 
portions;  these  send  off  four  slender  tendons,  which 
are 

Inserted,  the  first  tendon,  into  the  first  phalanx  of 
the  great  toe;  and  the  other  three  into  all  the  small 
toes,  except  the  little  one,  uniting  with  the  tendons  of 
the  extensor  digitorum  longus,  and  being  attached  to 
the  upper  convex  surface  of  all  the  phalanges. 

The  belly  of  this  muscle  lies  under  the  tendons  of 
the  extensor  digitorum  longus  and  peroneus  brevis;  it 
is  not,  however,  concealed,  but  is  seen  projecting 
behind  and  betwixt  these  tendons;  it  assists  in  form- 
ing the  tendinous  membrane  which  invests  the  upper 
surface  of  all  the  phalanges  of  the  toes. 

Its  use  is  to  extend  the  toes. 

It  is  sometimes  described  as  two  muscles,  the  ex- 
tensor brevis  pollicis  pedis,  and  extensor  brevis  digi- 
torum pedis. 


84  LONDON    DISSECTOR,  OR 


SECTION     II. 

DISSECTION    OF   THE    MUSCLES    ON    THE    POSTERIOR 
PART   OF    THE    LEG. 

THE  fascia  investing  the  posterior  part  of  the  leg,  is 

much  thinner  and  less  strong  than  that  on  the  fore  part. 

The  muscles  to  be  described  are  seven  in  number. 

1.  The  GASTROCNEMIUS  EXTERNUS,  or  GEMELLUS, 
Jlrises,  by  two  distinct  heads: — The  first,  or  Internal 
Head,  arises,  tendinous,  from  the  upper  and  back  part 
of  the  internal  condyle  of  the  os  femoris,  and  fleshy 
from  the  oblique  ridge  over  that  condyle.     The  sec- 
ond, or  External  Head,  arises,  in  the  same  manner, 
from  the  external  condyle.     Each  of  the  heads  forms 
a  fleshy  belly,  the  fibres  of  which  are  oblique,  passing 
from  a  tendinous  expansion  which  covers  the  posterior 
surface  of  the  muscle,  to  another  tendinous  expansion 
which  covers   the  anterior  surface,  or  that  surface 
which  lies  nearest  the  bones.     The  two  bellies,  of 
which  the  internal  is  much  the  larger,  are  separated 
by  a  considerable  triangular  space,  in  which  the  pop- 
liteal blood-vessels  and  nerves  pass  to  the  leg,  but  de- 
scending, they  unite  a  little  below  the  knee-joint  in  a 
middle  tendinous  line,  and  below  the  middle  of  the  tibia 
send  off  a  broad  flat  tendon,  which  unites  a  little  above 
the  ankle  with  the  tendon  of  the  soleus. 

Reflect  the  two  heads  of  the  gastrocnemius  from  the 
femoral  condyles,  and  you  will  then  expose, 

2.  The  SOLEUS,  or  GASTROCNEMIUS   INTERNUS — 
which  arises ,  by  two  origins  or  heads.     The  External, 
which  is  by  far  the  larger,  arises,  principally  fleshy, 
from  the  posterior  surface  of  the  head  of  the  fibula,  and 
from  the  external  angle  of  that  bone,  for  two-thirds  of 
its  length,  immediately  behind  the  peroneus  longus. 
The  internal  head,  arises,  fleshy,  from  an  oblique  ridge 


GUIDE    TO    ANATOMY.  85 

on  the  posterior  surface  of  the  tibia,  just  below  the  pop- 
liteus,  and  from  the  inner  angle  of  that  bone,  during  the 
middle  third  of  its  length.  The  two  heads  which  are 
at  first  separated  by  the  posterior  tibial  artery  and 
nerve,  unite  immediately,  forming  a  large  belly,  which, 
covered  by  the  tendon  of  the  gastrocnemius,  is  continu- 
ed, fleshy,  to  within  a  short  distance  of  the  ankle-joint; 
a  little  above  which,  the  tendons  of  the  gastrocnemius 
and  soleus  unite,  and  form  a  strong  round  tendon,  named 
the  TENDO  ACHILLIS,  which  slides  over  the  upper  and 
posterior  part  of  the  os  calcis,  where  it  is  furnished 
with  a  small  bursa  mucosa,  to  be 

Inserted  into  a  rough  surface  on  the  back-part  of  that 
bone. 

It  serves  to  elevate  the  os  calcis,  and  thereby  to  raise 
the  whole  body,  as  a  preparatory  measure  to  its  being 
carried  forward  in  progression;  to  carry  the  leg  back- 
wards on  the  foot  when  that  is  fixed;  the  gastrocnemi- 
us, from  its  origin  in  the  thigh,  also  bends  the  leg  on 
the  thigh. 

By  detaching  the  heads  of  the  gastrocnemius,  you 
will  expose, 

3.  The  PLANTARIS. — This  muscle  arises,  fleshy, 
from  the  upper  part  of  the  external  condyle  of  the  fe- 
mur and  its  oblique  ridge,  forms  a  pyramidial  belly 
about  three  inches  in  length,  which  adheres  to  the 
capsule  of  the  knee-joint,  runs  over  the  popliteus,  and 
terminates  in  a  long,  slender,  thin  tendon.  This  ten- 
don passes  obliquely  inwards  over  the  inner  head  of 
the  soleus,  and  under  the  gastrocnemius;  emerges  from 
between  those  two  muscles,  where  their  tendons  unite, 
and  then  runs  down  by  the  inside  of  the  tendo  Achillis, 
to  be 

Inserted  into  the  posterior  part  of  the  os  calcis,  on 
the  inside  of  the  insertion  of  the  tendo  Achillis,  and 
somewhat  before  it. 

8 


86  LONDON    DISSECTOR,  OR 

The  use  of  this  muscle  is  not  well  understood:  some 
say  that  it  serves  to  tuck  up  the  capsule  in  the  great 
bendings  of  the  knee-joint;  others,  that  it  assists  the 
gastrocnemii. 

4.  The   POPLITEUS — Arises ,  within  the  capsular 
ligament  of  the  knee,  by  a  round  tendon,  from  a  deep 
pit  or  hollow  on  the  outer  side  of  the  external  con- 
dyle;  adheres  to  the  posterior  and  outer  surface  of  the 
external  semilunar  cartilage;  passes,  within  the  cavity 
of  the  joint,  over  the  side  of  the  condyle  to  its  back 
part;  perforates  the  capsular  ligament,  and  forms  a 
fleshy  belly,  which   runs   obliquely   inwards,  being 
covered  by  a  thin  tendinous  fascia,  to  be 

Inserted,  broad,  thin  and  fleshy,  into  an  oblique 
ridge  on  the  posterior  surface  of  the  tibia,  a  little 
below  its  head,  and  into  the  triangular  space  above 
that  ridge. 

This  muscle  is  concealed  entirely  by  the  gastroc- 
nemius,  it  lies  above  the  inner  head  of  the  soleus;  and 
is  more  deeply  situated  than  the  plantaris,  which 
crosses  over  it. 

It  bends  the  leg,  and  when  bent,  rolls  it,  so  as  to 
turn  the  toes  inwards. 

The  belly  of  the  soleus  should  now  be  lifted,  in 
order  to  expose  the  deeply-seated  muscles.  A  strong 
membranous  fascia  is  seen  connecting  and  investing 
them,  which  is  to  be  removed. 

5.  The  FLEXOR  LONGUS  DIGITORUM  PEDIS  PER- 
FORANS — Arises,  fleshy,  from  the  posterior  flattened 
surface  of  the  tibia,  between  its  internal  and  external 
angles,  below  the  attachment  of  the  soleus,  and  con- 
tinues to  arise  from  the  bone  to  within  two  or  three 
inches  of  the  ankle;  the  fibres  pass  obliquely  into  a 
tendon  which  is  situated  on  the  posterior  edge  of  the 
muscle.     This  tendon  runs  behind  the  inner  ankle  in 
a  groove  of  the  tibia;  passes  under  a  strong  ligament 
which  goes  from  the  inner  ankle  to  the  os  calcis,  and 


GUIDE    TO    ANATOMY.  87 

having  received  a  strong  tendinous  slip  from  the  flexor 
pollicis  longus,  divides  about  the  middle  of  the  sole 
of  the  foot,  into  four  tendons,  which  pass  through  the 
slits  in  the  tendons  of  the  flexor  digitorum  brevis,  and 
are 

Inserted  into  the  extremity  of  the  last  joint  of  the 
four  toes. 

This  muscle  lies  on  the  inside  of  the  flexor  longus 
pollicis,  and  serves  to  bend  the  last  joint  of  the  toes, 
and  to  assist  in  extending  the  foot. 

6.  FLEXOR     LONGUS     POLLICIS    PEDIS — Arises^ 
fleshy,  from  the  posterior  flat  surface  of  the  fibula, 
continuing  its  origin  from  some  distance  below  the 
head  of  the  bone  to  within  an  inch  of  the  ankle.     The 
fleshy  fibres  terminate  in  a  tendon,  which  passes  behind 
the  inner  ankle  through  a  groove  in  the  tibia;  next 
through  a  groove  in  the  astragalus,  crosses  in  the  sole 
of  the  foot  the  tendon  of  the  flexor  longus  digitorum, 
to  which  it  gives  a  slip  of  tendon;  passes  between  the 
two  sesamoid  bones,  and  is 

Inserted  into  the  last  phalanx  of  the  great  toe. 

Its  office  is  to  bend  the  last  joint  of  the  great  toe^ 
and,  being  connected  by  a  cross  slip  to  the  flexor 
digitorum  communis,  to  assist  in  bending  the  other 
toes. 

7.  The  TIBIALIS  POSTICUS — Jlrises,  fleshy  from  the 
posterior  surface  of  both  the  tibia  and  fibula,  imme- 
diately below  the  upper  articulation  of  these  bones 
with  each  other;  from  the  whole  of  the  interosseous 
ligament;  from  the  angles  of  the  bones  to  which  that 
ligament  is  attached;  and  from  the  flat  surface  of  the 
fibula  behind  its  internal  angle  for  more  than  two-thirds 
of  its  length.      The  fibres  run  obliquely  towards  a 
middle  tendon,  which,  becoming  round,  passes  behind 
the  inner  ankle  through  a  groove  in  the  tibia. 

Inserted  into  the  upper  and  inner  part  of  the  os 
naviculare,  being  further  continued  through  a  groove  in 


88  LONDON    DISSECTOR,  OR 

that  bone  to  the  internal  and  external  cuneiform  bones; 
it  also  sends  some  tendinous  filaments  to  the  os  calcis, 
the  os  cuboides,  and  the  bases  of  the  metatarsal  bones 
supporting  the  second  and  middle  toe. 

This  muscle  may  be  said  to  arise  from  the  tibia  and 
fibula  before  the  interosseous  ligament,  as  its  fibres 
fill  up  a  perforation  in  the  upper  extremity  of  that 
ligament.  The  belly  is  concealed  at  its  lower  part 
by  the  flexor  longus  digitorum  and  flexor  pollicis,  and 
cannot  be  seen  till  those  muscles  are  separated.  It 
extends  the  foot,  and  turns  it  inwards. 


SECTION      III. 
DISSECTION    OF   THE    SOLE    OF  THE    FOOT. 

THE  cuticle  on  the  sole  of  the  foot  from  constant  pres- 
sure is  very  much  thickened;  betwixt  the  integuments 
and  plantar  aponeurosis,  we  find  a  tough  granulated 
fat,  which  adheres  firmly  to  the  aponeurosis,  and  is 
dissected  off  with  difficulty. 

APONEUROSIS,  or  FASCIA  PLANTARIS,  is  a  very  strong, 
tendinous  expansion,  which  arises  from  the  projecting 
extremity  of  the  os  calcis,  and  passes  to  the  root  of  the 
toes,  covering  and  supporting  the  muscles  of  the  sole 
of  the  foot.  Where  it  arises  from  the  heel,  it  is  thick, 
but  narrow;  as  it  runs  over  the  foot,  it  becomes  broad- 
er and  thinner;  and  it  is  fixed  to  the  the  head  of  each 
of  the  metatarsal  bones  by  a  bifurcated  extremity, which 
by  its  splitting,  leaves  room  for  the  tendons,  &c.  to  pass. 
It  seems  divided  into  three  portions,  which  are  con- 
nected by  strong  fasiculi  of  tendinous  fibres;  and  fibres 
are  sent  down,  forming  perpendicular  partitions  among 
the  muscles,  and  separating  them  into  three  classes; 


GUIDE    TO    ANATOMY.  89 

1.  The  middle  portion,  which  is  the  largest,  and 
under  which  are  contained  the  flexor  brevis  digitorum, 
and  the  tendons  of  the  flexor  longus  and  lumbricales. 

2.  The  external  lateral  portion,  which  covers  the 
muscles  of  the  little  toe. 

3.  The  internal  lateral  portion  concealing  the  mus- 
cles of  the  great  toe. 

On  removing  the  plantar  aponeurosis,  the  first  order 
of  muscles  in  the  sole  of  the  foot  is  exposed:  it  consists 
of  three  muscles. 

Abductor  Pollicis,  situated  on  the  side  of  the  great 
toe. 

Abductor  Minimi  Digiti,  on  the  side  of  the  little  toe. 

Flexor  Brevis  Digitorum  Pedis,  the  mass  in  the  mid- 
dle, situated  between  the  two  abductors. 

1.  ABDUCTOR  POLLICIS  PEDIS — JJrises,  tendinous 
and  fleshy,  from  the  lower  and  inner  part  of  the  os 
calcis;  from  a  ligament  which  extends  from  the  os  cal- 
cis  to  the  os  naviculare;  from  the  inside  of  the  os  navi- 
culare  and  cuneiforme  internum;  and  from  the  fascia 
plantaris. 

Inserted,  tendinous,  into  the  internal  sesamoid  bone, 
and  base  of  the  first  phalanx  of  the  great  toe. 

It  moves  the  great  toe  from  the  rest. 

2.  ABDUCTOR  MINIMI  DIGITI  PEDIS — Jlrises,  tendi- 
nous and  fleshy,  from  the  outer  side  of  the  os  calcis; 
and  from  a  strong  ligament,  which  passes  from  the  os 
calcis  to  the  metatarsal  bone  of  the  little  toe;  also  from 
the  fascia  plantaris. 

Inserted,  tendinous,  into  the  base  of  the  metatarsal 
bone  of  the  little  toe,  and  into  the  outside  of  the  base 
of  the  first  phalanx. 

This  muscle  can  frequently  be  divided  distinctly  into 
two  portions. 

It  moves  the  little  toe  from  the  rest. 

3.  FLEXOR  BREVIS  DIGITORUM  PEDIS  PERFORA- 
TUS — Arises,  fleshy,  from  the  anterior  and  inferior  part 

8* 


90  LONDON    DISSECTOR,  OR 

of  the  protuberance  of  the  os  calcis,  and  from  the 
inner  surface  of  the  fascia  plantaris;  also  from  the  ten- 
dinous partitions  betwixt  it  and  the  abductors  of  the 
great  and  little  toe: — it  forms  a  thick  fleshy  belly,  and 
sends  off  four  tendons,  which  split  for  the  passage  of  the 
tendons  of  the  flexor  longus  digitorum,  and  are 

Inserted  into  the  second  phalanx  of  the  four  lesser 
toes. 

The  tendon  of  the  little  toe  is  often  wanting. 

Its  use  is  to  bend  the  second  joint  of  the  toes. 

The  muscles  of  this  order  are  quite  superficial,  being 
only  covered  by  the  fascia  plantaris. 

These  being  removed,  or  lifted  from  their  origins, 
and  left  hanging  by  their  tendons,  the  second  order  is 
exposed. 

1 .  The  tendon  of  the  Flexor  longus  digitorum  pedis 
is  seen  coming  from  the  inside  of  the  os  calcis;  and, 
having  reached  the  middle  of  the  foot,  dividing  into  its 
four  tendons,  which  pass  through  the  slits  of  the  ten- 
dons of  the  flexor  digitorum  brevis.  and  are  inserted 
into  the  base  of  the  last  phalanx  of  the  four  toes. 

2.  The  tendon  of  the  Flexor  longus  pollicis  is  seen 
crossing  under*  the  tendon  of  the  flexor  longus  digito- 
rum, and,  having  given  to  it  a  short  slip  of  tendon,  pro- 
ceeding between  the  two  sesamoid  bones  to  the  base  of 
the  last  phalanx  of  the  great  toe. 

3.  FLEXOR  DIGITORUM   ACCESSORIUS,  or  Massa 
Carnea  JACOBI  SYLVII — Arises ,  fleshy,  from  the  sinu- 
osity at  the  inside  of  the  os  calcis,  and,  tendinous, 
from  that  bone  more  outwardly: — it  forms  a  belly  of 
a  square  form. 

Inserted  into  the  outside  of  the  tendon  of  the  flexor 
digitorum  longus,  just  at  its  division. 
It  assists  the  flexor  longus. 

*  In  the  erect  posture,  it  crosses  above,  lying  nearer  to  the  metatarsal 
bones  than  that  tendon;  but  in  the  description,  the  sole  of  the  foot  is  sup- 
posed to  be  placed  uppermost. 


GUIDE   TO    ANATOMY,  91 

4.  LUMBRICALES  PEDis — Arise,  by  four  tendinous 
and  fleshy  beginnings,  from  the  tendons  of  the  flexor 
longus  digitorum,  immediately  after  their  division. 

Inserted,  by  four  slender  tendons,  into  the  inside  of 
the  first  phalanx  of  the  four  small  toes,  and  into  the 
tendinous  expansion  that  is  sent  from  the  extensors  to 
cover  the  upper  part  of  the  toes. 

They  serve  to  promote  the  flexion  of  the  toes,  and 
to  draw  them  inwards. 

The  second  order  of  muscles  being  removed,  we 
expose  the  third  order. 

1 .  FLEXOR  BREVIS  POLLICIS  PEDIS. — It  arises,  ten- 
dinous, from  the  under  and  fore  part  of  the  os  calcis, 
where  it  joins  with  the  os  cuboides:  also,  from  the 
os   cuneiforme   externum;  it   forms   a   fleshy  belly, 
which  is  connected  inseparably  to  the  abductor  and 
adductor  pollicis. 

Inserted,  by  two  tendons,  into  the  external  and  inter- 
nal sesamoid  bones;  and  it  is  continued  on  into  the 
base  of  the  first  phalanx  of  the  great  toe.  It  bends 
the  first  joint  of  the  great  toe. 

2.  ADDUCTOR  POLLICIS  PEDIS — Arises,  tendinous 
and  fleshy,  from  a  strong  ligament  which  extends 
from  the  os  calcis  to  the  os  cuboides,  and  from  the 
roots  of   the   second,  third,  and   fourth    metatarsal 
bones;  it  forms  a  fleshy  belly,  which  seems  at  its 
beginning  divided  into  two  portions. 

Inserted,  tendinous,  into  the  external  sesamoid  bone, 
and  root  of  the  matatarsal  bone  of  the  great  toe. 
Used  to  bring  this  toe  nearer  the  rest. 

3.  FLEXOR  BREVIS  MINIMI  DIGITI  PEDIS — Arises, 
tendinous  and  fleshy,  from  the  os  cuboides,  and  from 
the  root  of  the  metatarsal  bone  of  the  little  toe. 

Inserted,  tendinous,  into  the  base  of  the  first  pha- 
lanx of  the  little  toe,  and  into  the  anterior  extremity 
of  the  metatarsal  bone.  Used  to  bend  this  toe. 

TRANSVERSALIS  PEDIS — Arises,  tendinous,   from 


92  LONDON    DISSECTOR,  OR 

the  anterior  extremity  of  the  metatarsal  bone  sup- 
porting the  little  toe;  becoming  fleshy,  it  crosses  over 
the  anterior  extremities  of  the  other  metatarsal  bones. 

Inserted,  tendinous,  into  the  anterior  extremity  of 
the  metatarsal  bone  of  the  great  toe,  and  into  the 
internal  sesamoid  bone,  adhering  to  the  adductor 
pollicis. 

It  contracts  the  foot,  by  approximating  the  toes. 

Ranging  with  this  order  of  muscles,  we  may  also 
observe  a  broad,  strong  ligament,  passing  from  the 
anterior  sinuosity  of  the  os  calcis  over  the  surface  of 
the  os  cuboides,  and  the  tendon  of  the  tibialis  pos- 
ticus,  dividing  into  numerous  tendinous  slips,  to  be 
inserted  into  the  bones  of  the  tarsus. 

Having  removed  the  muscles  last  described,  we 
expose  the  fourth  and  last  order. 

The  tendon  of  the  peroneus  longus  is  seen  passing 
along  a  groove  in  the  os  cuboides,  and  crossing  the 
tarsal  bones,  to  be  inserted  into  the  base  of  the  meta- 
tarsal bone  of  the  great  toe,  and  into  the  internal 
cuneiform  and  second  metatarsal  bones. 

INTEROSSEI  PEDIS  INTERNI,  are  three  in  number, 
situated  in  the  sole  of  the  foot.  They  arise,  tendi- 
nous and  fleshy,  from  between  the  metatarsal  bones 
of  the  four  small  toes,  and  are 

Inserted,  tendinous,  into  the  inside  of  the  base  of 
the  first  phalanx  of  each  of  the  three  small  toes. 

Used  to  move  the  three  smaller  toes  inwards 
towards  the  great  toe. 

INTEROSSEI  PEDIS  EXTERNI,  are  four  in  number, 
larger  than  the  internal  interossei,  and  situated  on  the 
back  of  the  foot;  they  are  bicipites,  or  arise  by  two 
slips. 

Arise,  tendinous  and  fleshy,  between  the  metatarsal 
bones  of  all  the  toes. 

Inserted^  the  first,  abductor  indicis  pedis,  into  the 
inside  of  the  base  of  the  first  phalanx  of  the  fore-toe; 


GUIDE    TO    ANATOMY.  93 

the  second,  adductor  indicis  pedis,  into  the  outside  of 
the  same  toe; — the  third,  adductor  medii  digiti  pedis, 
into  the  outside  of  the  middle  toe; — the  fourth,  adduc- 
tor tertii  digiti  pedis,  into  the  outside  of  the  third  toe. 
Used  to  separate  the  toes. 


CHAPTER  VI. 

DISSECTION  OF  THE  UPPER  PART 
OF  THE  BODY. 

SECTION    I. 
THE    EXTERNAL    PARTS    OF   THE    HEAD. 

THE  integuments  of  the  head  are  thick,  and  covered 
with  hair,  having  beneath  the  cutis  a  condensed  cel- 
lular substance,  which  is  closely  connected  with  the 
epicranium,  or  expanded  tendon  of  the  occipito-fronta- 
lis,  and  renders  the  dissection  of  that  muscle  difficult. 

The  only  muscle,  which  properly  belongs  to  the 
hairy  scalp,  is  a  single  broad  digastric  muscle,  viz: 

OCCIPITO-FRONTALIS.  It  arises  fleshy  and  tendinous, 
from  the  transverse  ridge  of  the  occipital  bone,  as  far 
forward  as  the  mastoid  process;  forming  a  broad  thin 
tendon,  which  covers  the  whole  upper  part  of  the 
cranium;  it  is 

Inserted,  fleshy,  on  each  side,  into  the  orbicularis 
palpebrarum,  the  skin  of  the  eye-brows,  and  the 
internal  angular  process  of  the  os  frontis  and  os  nasi. 

The  tendon  of  this  muscle  adhering  firmly  to  the 
skin,  and  but  loosely  to  the  pericranium,  enables  it  to 


94  LONDON    DISSECTOR,  OR 

raise  the  eye-brows,  and  corrugate  the  skin  of  the 
forehead. 

The  muscles  of  the  external  ear  are  not  always  so 
distinct  as  to  admit  of  a  clear  demonstration. 

(1)  ATTOLLENS  AUREM,  or  the  Superior  auris — 
Arises  from  the  tendon  of  the  occipito-frontalis,  and 
from  the  aponeurosis  of  the  temporal  muscle. 

Inserted  into  the  upper  part  of  the  root  of  the  car- 
tilage of  the  ear,  opposite  to  the  antihelix. 

Used  to  draw  the  ear  upwards. 

(2.)  ANTERIOR  AURIS — Arises,  thin  and  membra- 
nous, from  the  posterior  part  of  the  zygomatic  process 
of  the  temporal  bone. 

Inserted  into  a  small  eminence  on  the  back  of  the 
helix,  opposite  to  the  concha. 

Use:  To  draw  the  eminence  a  little  forwards  and 
upwards. 

(3.)  The  RETRAHENTES  AURIS,  or  Posterior  auris — 
Jlrises  by  two  or  three  distinct  slips,  from  the  external 
and  posterior  part  of  the  mastoid  process,  immedi- 
ately above  the  insertion  of  the  sterno-cleido  mastoi- 
deus. 

Inserted  into  that  back  part  of  the  ear  which  is 
opposite  to  the  septum,  dividing  the  scapha  and 
concha. 

Use:  To  draw  the  ear  back,  and  stretch  the  concha. 

The  proper  muscles  of  the  ear  are  next  to  be 
described;  but  the  student  must  not  expect  to  meet 
with  them  distinctly  marked  in  every  subject;  in 
general  they  are  very  confused  and  indistinct. 

(1.)  HELICIS  MAJOR — Arises  from  the  upper  and 
acute  part  of  the  helix,  anteriorly. 

Inserted  into  its  cartilage,  a  little  above  the  tragus. 

Use:  To  depress  the  part  from  which  it  arises. 

(2.)  HELICIS  MINOR — Arises  from  the  inferior  and 
anterior  part  of  the  helix. 


GUIDE    TO    ANATOMY.  95 

Inserted  into  the  crus  of  the  helix,  near  the  fissure 
in  the  cartilage  opposite  to  the  concha. 

Use:  To  contract  the  fissure. 

(3.)  TRAGICUS — Jlrises  from  the  middle  and  outer 
part  of  the  concha,  at  the  root  of  the  tragus,  along 
which  it  runs. 

Inserted  into  the  point  of  the  tragus. 

Use:  To  pull  the  point  of  the  tragus  a  little 
forwards. 

(4.)  ANTITRAGICUS — Mses  from  the  internal  part 
of  the  cartilage  that  supports  the  antitragus;  and, 
running  upwards,  is 

Inserted  into  the  tip  of  the  antitragus  as  far  as  the 
inferior  part  of  the  antihelix. 

Use:  To  turn  the  tip  of  the  antitragus  a  little  out- 
wards, and  depress  the  extremity  of  the  antihelix 
towards  it. 

(5.)  TRANSVERSUS  AURIS — Jlrises  from  the  promi- 
nent part  of  the  concha  on  the  dorsum  of  the  ear. 

Inserted  opposite  to  the  outer  side  of  the  antihelix. 

Use:  It  draws  the  parts  to  which  it  is  connected 
towards  each  other,  and  stretches  the  scapha  and 
concha. 

The  muscles  of  the  internal  ear  are  situated  within 
the  temporal  bone  itself;  they  are  very  small,  and 
can  be  seen  only  when  the  internal  parts  of  the  organ 
of  hearing  are  prepared;  but  their  description  is 
necessary  to  complete  the  history  of  the  muscles. 

(1.)  LAXATOR  TYMPANI — Arises,  by  a  small  origin, 
from  the  spinous  process  of  the  sphenoid  bone,  and 
the  side  of  the  Eustachian  tube.  It  runs  backwards, 
and  a  little  upwards,  along  with  the  nerve  called 
Chorda  Tympani,  in  a  fissure  of  the  glenoid  or  articu- 
lar cavity  of  the  os  temporis. 

Inserted  into  the  long  process  of  the  malleus. 

Use:  To  draw  the  malleus  obliquely  forwards  to- 
wards its  origin,  and  consequently  the  membrana 


96  LONDON    DISSECTOR,  OR 

tympani  by  which  that  memhrane  is  made  less  con- 
cave, or  is  relaxed. 

(2.)  TENSOR  TYMPANI — Arises,  tby  a  small  fleshy 
beginning,  from  the  cartilaginous  extremity  of  the 
Eustachian  tube,  just  where  it  begins  to  be  covered 
by  the  pars  petrosa  and  spinous  process  of  the  sphe- 
noid bone,  and  runs  along  the  bony  half-canal  of  the 
typanum,  where  it  is  invested  by  a  membranous 
vagina. 

Inserted  into  the  neck  of  the  malleus,  above  the 
small  process,  and  even  as  far  as  the  handle. 

Use:  To  draw  the  malleus  and  membrana  tympani 
towards  the  pars  petrosa,  and  thus  render  the  mem- 
brane more  concave  and  tense. 

A  third,  but  much  less  distinct  muscle,  has  been 
described,  under  the  name  of  EXTERNAL  or  SUPERIOR 
MUSCLE  of  the  malleus. 

It  arises  from  the  internal,  superior,  and  posterior 
part  of  the  meatus  externus,  to  be  fixed  by  a  small 
tendon  to  the  neck  of  the  malleus. 

3.  STAPEDIUS  is  a  short  and  thick  muscle.  It 
arises  from,  and  lies  concealed  within,  the  small  bony 
pyramid  at  the  bottom  of  the  tympanum;  the  cavity 
which  it  fills  is  near  the  bony  canal  for  the  portio 
dura  of  the  auditory  nerve.  It  terminates  in  a  small 
tendon,  which  passing  out  of  the  cavity  through  the 
small  hole  in  the  apex  of  the  pyramid,  runs  forwards, 
and  is 

Inserted  into  the  neck  of  the  stapes,  on  the  sides  of 
the  longest  and  most  crooked  leg  of  that  bone. 

Use:  To  draw  the  stapes  obliquely  upwards  to- 
wards the  pyramid,  by  which  the  posterior  part  of 
its  base  is  moved  inwards,  and  the  anterior  part 
outwards. 


GUIDE    TO    ANATOMY.  97 


SECTION     II. 

OF  THE    CONTENTS    OF  THE    CRANIUM,  OR    THE  BRAIN 
AND    ITS    MEMBRANES. 

A  transverse  incision,  extending  from  ear  to  ear 
over  the  crown  of  the  head,  being  made  through  the 
tendon  of  the  occipito-frontalis,  the  two  flaps  may, 
with  facility,  be  inverted  on  the  face  and  neck. 
Remove  the  superior  part  of  the  cranium  by  a  saw 
directed  anteriorly  through  the  frontal  bone  above  the 
orbitar  process,  and  posteriorly  as  low  as  the  trans- 
verse ridge  of  the  occipital  bone. 

When  the  superior  part  of  the  cranium,  commonly 
called  the  Calvarium,  or  skull-cap,  has  been  torn  off, 
for  which  considerable  force  is  requisite,  you  expose 
the  DURA  MATER,  a  firm,  compact,  and  whitish  mem- 
brane, somewhat  shining,  rough  on  its  outer  surface, 
from  the  rupture  of  vessels  which  connected  it  to  the 
cranium,  and  covered  with  bloody  spots  in  conse- 
quence of  the  blood  effused  from  these  ruptured  ori- 
fices. It  is  described  as  being  separable  into  many 
laminae;  two,  however,  with  facility,  may  be  demon- 
strated; and  it  4s  said  that  these  two  laminae,  by 
separating  and  re-uniting,  form  the  triangular  cavities, 
named  Sinuses,  which  are,  in  fact,  large  veins.  This 
division  of  layers  can  hardly  be  admitted  as  correct 
in  the  recent  state  of  the  membrane. 

The  SUPERIOR  LONGITUDINAL  SINUS  lies  in  a 
groove  formed  by  the  two  parietal  bones;  it  extends 
along  the  sagittal  suture  from  the  crista  galli  of  the 
ethmoid  bone  to  the  middle  of  the  os  occipitis,  where 
it  bifurcates  into  the  two  lateral  sinuses;  in  its  passage 
backwards,  its  size  is  increased.  When  slit  open,  its 
triangular  form  is  evident;  it  is  lined  by  a  smooth 
membrane,  and  in  it  may  be  remarked  the  numerous 
9 


98  LONDON    DISSECTOR,  OR 

openings  of  the  veins  of  the  pia  mater,  the  frena,  or 
slips  of  fibres  crossing  from  side  to  side,  the  glandulae 
Pacchioni  internae  et  externae,  which  are  little  bodies 
like  millet-seed,  seen  on  the  outer  and  inner  surface  of 
the  sinus. 

The  arteries  of  the  dura  mater  are  divided  into  the 
anterior,  middle,  and  posterior. 

1.  ARTERIA  MENINGEA    MEDIA  (called  also  the 
Spinalis  or  Spheno-spinalis)  the  great  middle  artery,  is 
a  branch  of  the  internal  maxillary;  it  passes  through 
the  spinous  hole  of  the  sphenoid  bone,  and  is  seen  rising 
from  the  anterior  inferior  angle  of  the  parietal  bone 
(in  a  groove  of  which  it  lies,)  and  spreading  its  nume- 
rous branches  over  the  dura  mater. 

The  anterior  and  posterior  arteries  are  small. 

2.  A.  MENINGEA  ANTERIOR  is  sent  off  from  the  ex- 
ternal carotid,  and  enters  the  cranium  by  the  foramen 
lacerum  orbitale  superius. 

3.  A.  MENINGEA  POSTERIOR  is  given  off  by  the 
vertebral  artery;  the  dura  mater  also  receives  small 
twigs  from  the  occipital,  pharyngeal  arteries,  &c. 

The  nerves  of  the  dura  mater  are  said  to  come  from 
the  fifth  pair;  if  they  exist  at  all,  they  are  small,  and 
seldom  demonstrated. 

OF    THE    SEPTA    OF    THE    BRAIN,    OR    PROCESSES    OF 
THE    DURA    MATER.* 

1.  The  FALX  (septum  sagittale,  verticale,  mediasti- 
num cerebri  or  falciform  process)  is  a  long,  broad  fold, 
or  duplicature  of  the  inner  lamina  of  the  dura  mater, 
dividing  the  cerebrum  into  two  hemispheres,  extend- 
ing from  the  crista  galliof  the  ethmoid  bone,  along  the 

*  To  demonstrate  these,  the  dura  mater  should  be  divided  in  the  line 
of  the  division  of  the  cranium:  its  internal  surface  will  be  found  smooth, 
glistening,  and  free  from  adhesion,  except  in  the  course  of  the  longitudi- 
nal sinus,  into  which  veins  pass  from  the  pia  mater. 


GUIDE    TO    ANATOMY.  99 

middle  of  the  os  frontis  and  point  of  junction  of  the  two 
parietal  bones, to  the  crucial  ridge  of  the  occipital  bone, 
where  it  terminates  in  the  middle  of  the  next  septum. 

2.  The  TENTORIUM  CEREBELLI,  or  transverse  sep- 
tum.    This  separates  the  cerebrum  from  the  cerebel- 
lum, and  is  formed  by  the  inner  lamina  of  the  dura  ma- 
ter, reflected  off'  from  the  os  occipitis  along  the  groove 
of  the  lateral  sinuses,  and  the  edge  or  angle  of  the  tem- 
poral bones.     It  is  frequently  called  Tentorium  Cere- 
bello  Super  Extensum.     Its  position  is  horizontal. 

There  are  some  other  folds  of  the  dura  mater,  not 
visible  in  this  stage  of  the  dissection,,  viz: 

3.  The  falx  of  the  cerebellum,  or  small  occipital  sep- 
tum, which  will  be  seen  when  the  cerebrum  is  removed. 
It  extends  from  the  middle  of  the  tentorium  along  the 
middle  spine  of  the  os  occipitis  to  the  foramen  magnum, 
dividing  the  cerebellum  into  two  parts. 

4.  The  sphenoidal  folds,  two  small  folds  of  the  dura 
mater,  one  on  each  side  of  the  sella  turcica,  stretching 
from  the  posterior  to  the  anterior  clinoid  processes. 

The  dura  mater  also,  in  many  parts  of  the  brain, 
separates  its  laminae  to  form  sinuses;  the  principal  of 
these  will  be  noticed  in  the  course  of  the  dissection. 

Detach  the  falx  from  the  crista  galli,  and  turn  it  back- 
wards; observe  in  its  lower  edge  the  INFERIOR*  LON- 
GITUDINAL SINUS,  which  enters  a  sinus  in  the  Tento- 
rium, termed  Torcular  Hierophili,  or  straight  sinus. 
This  will  fully  expose  the  convolutions  of  the  brain, 
which  are  closely  invested  by  the  pia  mater. 

The  next  membrane  which  we  meet  is  the  TUNICA 
ARACHNOIDES.  It  is  a  transparent  membrane,  cover- 
ing uniformly  the  surface  of  the  pia  mater,  without 
passing  into  the  interstices  of  its  duplicatures.  It  is 
attached  to  it,  is  extremely  thin,  without  vessels,  de- 
monstrated with  difficulty  on  the  upper  surface  of  the 
brain  by  the  blow-pipe  (which  raises  it  into  cells,)  but 
on  the  base  of  the  brain  it  can  be  distinctly  seen. 


100  LONDON    DISSECTOR,  OR 

Beneath  the  last  membrane  is  found  the  Pia  Mater, 
or  tunica  vasculosa,  a  very  vascular  membrane,  trans- 
parent in  the  interstices  of  its  vessels,  investing  the  sub- 
stance of  the  brain,  descending  betwixt  all  its  convo- 
lutions, and  lining  its  different  cavities;  but.  where  it 
lines  the  ventricles  it  is  fine,  delicate,  and  less  vascu- 
lar, than  on  the  surface,  and  betwixt  the  convolutions 
of  the  brain:  It  is  connected  to  the  dura  mater  by  its 
veins  passing  into  the  longitudinal  sinus. 

The  brain  is  divided  into  three  parts:  The  cere- 
brum; the  cerebellum;  and  the  medulla  oblongata. 

The  CEREBRUM  consists  of  two  distinct,  substances: 

1 .  The  cineritious  or  cortical  substance  forming  the 
outer  part. 

2.  The  white  or  medullary  substance  forming  the 
inner  part 

The  brain  is  divided  by  the  falx  into  two  hemis- 
pheres, and  by  the  pia  mater  into  numerous  convolutions. 

Each  hemisphere  is  divided  into  three  lobes. 

The  ANTERIOR  LOBES  rest  on  that  part  of  the  cra- 
nium which  forms  the  two  orbits,  and  is  called  the 
anterior  fossae  of  the  basis  of  the  cranium. 

The  MIDDLE  LOBES  are  situated  before  and  above 
the  medulla  oblongata,  and  rest  on  the  middle  fossseof 
the  basis  crariii,  which  are  formed  by  the  sphenoid  and 
temporal  bones. 

The  POSTERIOR  LOBES  are  supported  by  the  ten- 
torium. 

The  anterior  and  middle  lobes  are  parted  by  a  deep 
narrow  sulcus,  which  ascends  obliquely  backwards 
from  the  temporal  ala  of  the  os  sphenoides  to  near  the 
middle  of  the  os  parietale;it  is  termed  FISSURA  CERE- 
BRI,  or  Fissura  Magna  Silvii. 

By  gently  separating  with  the  fingers  the  two  hemis- 
pheres of  the  brain,*  we  see  passing  betwixt  them  a 

*  Between  the  hemispheres  and  on  the  surface  of  the  corpus  callosum, 
we  observe,  if  the  arteries  are  injected,  the  arteriae  callosse,  which  are 
the  continuation  of  the  trunks  of  the  anterior  cerebri. 


GUIDE    TO    ANATOMY.  101 

longitudinal  white  convex  body,  the  CORPUS  CALLO- 
SUM;  it  lies  under  the  falx,  incurvates  downwards  at 
both  its  extremities,  and  is  continued  anteriorly  into  the 
medullary  substance  betwixt  the  corpora  striata,  pos- 
teriorly into  the  fornix  and  inferior  cornu  of  the  lateral 
ventricle  on  each  side.  From  its  connecting  the  two 
hemispheres  it  is  called  the  Commissura  Magna.  On 
the  surface  of  the  corpus  callosum  is  seen  the  RAPHE, 
formed  by  two  longitudinal  medullary  lines  united  by 
transverse  fibres. 

When  the  brain  is  cut  horizontally  on  a  level  with 
the  corpus  callosum,  an  appearance  is  produced, 
termed  the  Medullary  arch,  or  CENTRUM  OVALE. 
When  only  one  of  the  hemispheres  is  sliced  off  to  this 
level,  the  appearance  presented  by  the  medullary 
substance  is  called  the  centrum  ovale  parvum  of  Vicq 
d'Azyr. 

Under  this  arch  are  the  two  lateral  ventricles.*  If 
one  of  these  be  cautiously  perforated  on  the  side  of 
the  corpus  callosum,  and  gently  inflated  by  a  blow- 
pipe, its  extent  may  be  seen;  but,  if  much  force  be 
used,  the  air  will  pass  into  the  other  ventricle. 

The  two  ventricles  are  separated  by  a  medullary 
partition,  which  descends  from  the  inferior  surface  of 
the  corpus  callosum  to  the  fornix,  and  is  called  the 
SEPTUM  LUCIDUM;  it  consists  of  two  laminae,  with  a 
narrow  cavity  between.  To  see  this  septum,  one  of 
the  ventricles  must  be  laid  open,  and  the  septum  pulled 
gently  to  the  other  side. 

The  LATERAL  VENTRICLES  are  two  in  number,  the 
right  and  the  left,  lined  with  a  fine  membrane,  narrow, 
consisting  of  a  body,  and  three  prolongations  or  cor- 
nua. 

*  To  show  the  lateral  ventricles,  the  corpus  callosum  should  be  cut 
away  close  to  the  septum  lucidum;  and  then,  the  ventricle  of  that  body, 
and  the  thickness  and  breadth  of  the  septum  itself,  will  ba  more  clear!  y 
seen. 

9* 


102  LONDON    DISSECTOR,  OR 

1 .  The  body  is  formed  betwixt  the  corpus  callosum, 
the  medulla  of  the  brain,  the  convexity  of  the  corpus 
striatum,  and  the  thalamus  nervi  optici. 

2.  The  anterior  cornu  or  horn  is  formed  betwixt 
the  more  acute  convexity  of  the  corpus  striatum,  and 
the  anterior  part  of  the  corpus  callosum. 

3.  The   posterior   cornu   (called   also  the  digital 
cavity)  may  be  traced  stretching  backwards  and  down- 
wards into  the  posterior  lobe  of  the  brain. 

4.  The   inferior   or   descending   cornu  cannot  be 
traced  in  this  stage  of  the  dissection;  it  seems  like  the 
continued  cavity  of  the  ventricle,  takes  a  curve  back- 
wards  and   outwards,   and   then,   turning  forwards, 
descends  into  the  middle  lobe  of  the  brain. 

The  lateral  ventricles  communicate  with  each  other, 
and  with  the  third  ventricle,  by  an  opening  under  the 
fore  part  of  the  arch  of  the  fornix,  called  the  foramen 
commune  anterius* 

In  the  lateral  ventricles  we  meet  with 
The  FORNIX,  a  medullary  body,  flat,  and  of  a  tri- 
angular shape;  which  divides  the  two  laterai  and  the 
third  ventricles.  It  is  exposed  on  tearing  away  the 
septum  lucidum;  its  lower  surface  is  towards  the  third 
ventricle;  its  lateral  margins  are  in  the  lateral  ventri- 
cles; on  its  upper  surface  it  supports  the  septum  luci- 
dum, and  under  its  most  anterior  part  is  the  foramen 
Monroianum: — One  of  the  angles  of  this  body  is  for- 
ward, and  the  other  two  towards  the  back  part;  it 
rests  chiefly  on  the  thalami  nervorum  opticorum,  but 

*  It  has  been  doubted  whether  or  not  this  be  an  opening;  the  choroid 
plexus  passes  through  it,  and  seems  to  unite  the  surfaces;  it  is  absurdly 
named  the  Foramen  Monroianum,  from  a  mistaken  notion  that  Dr.  Monro 
discovered  it,  and  may  be  seen  by  gently  turning  the  anterior  crus  of  the 
fornix  to  one  side;  it  is  a  space  be'twixt  the  most  anterior  part  of  the  con- 
vexity of  the  thalami  nervorum  opticorum,  and  the  anterior  crus  of  the 
fornix. 

This  foramen  may  always  be  easily  found  by  following  the  course  of 
the  plexus  choroides,  as  it  passes  forwards  in  the  ventricle.  It  is  a  slit, 
rather  than  a  round  hole,  in  the  natural  state. 


GUIDE   TO   ANATOMY.  103 

is  separated  from  them  by  a  vascular  membrane  called 
the  velum. 

The  extremities  of  the  body  of  the  fornix  are  named 
its  Crura. 

1 .  The  crus  anterius  is  double,  bends  downwards 
before  the  anterior  commissure  of  the   brain,  with 
which  it  is  connected,  and  maybe  traced  into  the  cor- 
pora albicantia. 

2.  The  two  crura  posteriora,  coalescing  with  the 
back  part  of  the  corpus  callosum,  pass,  on  each  side, 
into  the  inferior  cornu  of  the  lateral  ventricle,  and 
terminate  in  a  pointed  form  on  the  hippocampus  major. 

Divide  the  body  of  the  fornix,  invert  it,  by  turning 
the  anterior  crus  forwards,  and  the  posterior  crura 
backwards;  on  the  under  surface  of  the  latter  is  an 
appearance  of  transverse  lines,  named  Corpus  Psal- 
loides,  psalterium,  or  lyra. 

The  inversion  of  the  fornix  exposes 

The  PLEXUS  CHOROIDES. — This  is  a  continuation 
of  the  pia  mater,  a  spongy  mass,  consisting  of  folds  of 
tortuous  vessels,  partly  covering  the  thalami  nervorum 
opticorum,  and  continued  into  the  inferior  cornu  of 
the  lateral  ventricles.  The  plexus  of  each  side  is 
connected  to  its  fellow  by  the  velum  interpositum,  a 
membrane  which  passes  under  the  fornix,  and  lies  on 
the  third  ventricle  and  corpora  quadrigemina. 

From  this  plexus  the  blood  is  received  by  the  VENA 
GALENI,  situated  in  the  middle  of  the  velum  which 
consists  of  two  parallel  branches;  these  run  backwards, 
unite,  and  enter  the  fourth  sinus  of  the  dura  mater, 
called  TORCULAR  HIEROPHILI. 

This  plexus  should  now  be  detached  at  its  fore  part, 
and  turned  back:  it  will  remain  as  a  guide  to  the  knife 
in  tracing  the  inferior  cornu  of  the  lateral  ventricle. 

We  now  se'e 

The  CORPORA  STRIATA,  two  smooth  cineritious 
convexities,  in  the  fore  part  of  the  lateral  ventricle, 


104  LONDON    DISSECTOR,  OR 

broad,  and  rounded  anteriorly,  becoming  narrow,  and 
diverging  as  they  pass  backwards,  consisting  of 
medullary  and  cortical  substance  disposed  in  striae. 

The  THALAMI  NERVORUM  OPTICORUM,  two  large 
oval,  whitish  eminences,  placed  by  the  side  of  each 
other  between  the  diverging  extremities  or  crura  of 
the  corpora  striata;  towards  their  fore  part  is  a  peculiar 
eminence  or  convexity,  called  the  Anterior  Tubercle 
or  Monticulus;  they  are  elongated  downwards,  to  form 
the  optic  nerves. 

The  T^ENIA  SEMICIRCULARIS,  is  a  white  medullary 
line,  running  in  the  angle  betwixt  the  corpus  striatum 
and  thalamus  nervi  optici  of  each  side. 

The  COMMISSURA  ANTERIOR  CEREBRI,  is  a  short 
cylindrical  medullary  cord,  stretched  transversely 
between  the  fore  and  lower  part  of  the  corpora  striata, 
immediately  under  the  anterior  crura  of  the  fornix. 

Just  above  the  commissura  anterior,  and  before 
the  thalami,  is  the  VULVA,  or  foramen  commune  ante- 
rius,  a  small  slit  or  indentation,  formed  by  the  anterior 
crus  of  the  fornix,  bifurcating,  and  inserting  itself,  on 
each  side,  between  the  corpus  striatum  and  thalamus 
nervi  optici.  This  slit  is  the  space  by  which  the 
three  ventricles  communicate. 

The  COMMISSURA  MOLLIS  is  an  exceedingly  soft, 
broad,  cineritious  junction  betwixt  the  convex  surfaces 
of  the  thalami  nervorum  opticorum. 

On  separating  the  optic  thalami,  we  discover  the 
THIRD  VENTRICLE.  This  is  a  longitudinal  sulcus,  or 
slit,  situated  betwixt  the  thalami  nervorum  opticorum, 
and  betwixt  the  crura  cerebri.  Above,  it  is  covered 
by  the  fornix  and  velum  interpositum;  at  its  upper  and 
fore  part,  it  communicates  with  the  two  lateral  ven- 
tricles; below  the  commissura  anterior,  it  opens  into 
the  infundibulum.  This  opening  is  termed  iter  ad 
infundibulum.  Backwards,  it  is  continued  by  a  canal 
which  passes  under  the  tubercula  quadrigemina  into 


GUIDE    TO    ANATOMY.  105 

the  fourth  ventricle.  This  passage  is  named  iter  ad 
quartum  ventriculum,  aquaeductus  Sylvii,  or  canalis- 
medius. 

The  ANUS,  or  foramen  commune  posterius,  is  situ- 
ated behind  the  commissure  of  the  optic  thalami,  and 
before  the  corpora  quadrigemina.  It  is  closed  up  by 
the  velum  interpositum,  and,  when  that  is  removed, 
leads  into  the  back  part  of  the  third  ventricle. 

The  PINEAL  GLAND,  a  small,  soft,  greyish,  and 
conical  body,  of  the  size  of  a  pea,  is  seated  above  the 
tubercula  quadrigemina,  and  behind  the  thalami, 
to  which  it  is  connected  by  two  white  pedunculi,  or 
foot-stalks;  its  base  is  turned  forwards,  and  the  apex 
backwards;  it  is  covered  by  the  plexus  choroides  and 
posterior  crura  of  the  fornix.  It  contains  an  earthy 
matter,  either  in  its  own  substance,  or  that  of  the 
pedunculi,  resembling  sand,  and,  when  viewed  by  a 
magnifier,  assuming  a  granulated  and  clear  light 
yellow  appearance.  It  was  named  by  Scemmerring, 
who  first  discovered  that  it  belongs  to  the  healthy 
structure  of  the  brain,  the  ACERVULUS  GLANDU.LJE 

PlNEALIS. 

The  COMMISSURA  POSTERIOR  is  a  transverse  cord 
at  the  back  part  of  the  third  ventricle,  before  the  tu- 
bercula quadrigemina,  and  above  the  iter  ad  quartum 
ventriculum. 

TUBERCULA  QuADRi&EMiNA,four  small  white  bodies, 
adhering  together,  lying  under  the  pineal  gland,  behind 
the  third  ventricle,  and  above  the  fourth.  The  upper- 
most two  are  named  NATES,  and  the  other  two  TESTES. 

From  the  under  part  of  the  testes,  there  projects 
backwards,  connecting  itself  with  the  crura  cerebelli, 
a  thin  medullary  lamina,  which  is  the  valvula  Vieus- 
senii,  called  also  processus  a  cerebello  ad  testes,  velum 
interjectum,  valvula  major. 

The  inferior  cornu  of  the  lateral  ventricle,  which 
descends  into  the  middle  lobe  of  the  brain,  may  now  be 


106  LONDON    DISSECTOR,  OR 

traced,  by  following  the  tract  of  the  choroid  plexus;* 
in  it  is  seen 

The  HIPPOCAMPUS  MAJOR,  or  Cornu  Ammonis.  At 
its  commencement  it  is  narrow,  but  it  becomes  a  broad 
medullary  projection  of  the  floor  of  the  ventricle,  and 
its  extremity,  which  is  called  PES  HIPPOCAMPI,  is 
curved  inwards.  The  thin  edge  on  its  inside,  which 
follows  the  whole  of  its  circuit,  is  named  the  CORPUS 
FIMBRIATUM,  or  Taenia  Hippocampi.  The  posterior 
crus  of  the  fornix  runs  along  its  inner  and  anterior  part, 
in  the  form  of  a  thin  floating  edge. 

In  the  posterior  cornu  of  the  lateral  ventricle,  which 
passes  into  the  posterior  lobe  of  the  brain,  there  is  a 
similar  medullary  projection,  but  smaller,  the  HIPPO- 
CAMPUS MINOR. 

In  the  anterior  part  of  the  third  ventricle,  below  the 
iter  ad  infundibulum,  are  seen  the  CORPORA  ALBI- 
CANTIA  Willisii  (corpora  mamillaria  or  subrotunda,) 
two  medullary  eminences  of  the  size  of  peas;  the 
remainder  of  these  bodies  is  seen  on  the  outer  surface 
of  the  base  of  the  brain. 

This  completes  the  demonstration  of  the  cerebrum. 
The  whole  of  the  posterior  lobes,  and  the  lateral  part 
of  the  middle  lobes,  may  be  removed.  This  exposes 
to  your  view, 

The  TENTORIUM,  and  the  FALX  CEREBELLI.  At 
this  point  you  should  trace  the  bifurcation  of  the  lon- 
gitudinal sinus  into  the  two  lateral  sinuses.  The  lateral 
sinuses  are  formed  by  the  splitting  of  the  laminae  of 
the  tentorium;  hence  they  follow  the  course  of  that 
membrane,  run  along  their  grooves  in  the  occipital 
bone,  and  dip  downwards  and  forwards  through  the 
foramen  lacerum  in  basi  cranii,  to  terminate  in  the 
internal  jugular  veins. 

*  Or  it  may  be  exhibited  by  cutting  away  successive  slices  of  the  side 
of  the  brain,  until  the  ventricle  is  exposed. 


GUIDE    TO    ANATOMY.  107 

The  TORCULAR  HIEROPHILI,  or  fourth  sinus,  runs 
along  the  middle  of  the  tentorium,  and  joins  the  ex- 
tremity of  the  longitudinal  sinus  at  the  point  where  it 
bifurcates. 

The  great  notch  of  the  tentorium  is  a  circular  open- 
ing left  on  the  anterior  part  of  the  tentorium,  allow- 
ing a  junction  between  the  cerebrum  and  cerebellum. 

Proceed  next  to  the  examination  of  the  cerebellum; 
and,  in  order  to  accomplish  this  demonstration,  it  will 
he  convenient  to  remove  the  posterior  part  of  the  os 
occipitis, 

CEREBELLUM. — This  part  of  the  brain,  divided  into 
two  lobes  by  the  falx  cerebelli,  or  septum  occipitale, 
is  covered  by  a  vascular  membrane;  consists  of  me- 
dullary and  cineritious  substance;  but  instead  of  convo- 
lutions, has  numerous  deep  sulci,  into  which  the  pia 
mater  dips,  and  forms  thin  flat  strata. 

Remark  the  following  processes: 

1.  Appendix,  vel  processus  vermiformis  superior, 
situated  under  the  pia  mater,  on  the  anterior  and  supe- 
rior part  of  the  cerebellum. 

2.  Appendix,  or  processus  vermiformis  posterior,  will 
be  found  situated  between  the  two  lobes  on  the  under 
surface  of  the  cerebellum,  and  immediately  behind  the 
medulla  oblongata. 

On  separating  the  two  lobes  behind,  and  making  a 
deep  incision,  we  discover 

The  FOURTH  VENTRICLE. — The  sides  of  this  ven- 
tricle are  formed  by  the  cerebellum,  the  anterior  part 
by  the  medulla  oblongata,  the  upper  and  back  part  by 
the  valvula  cerebri;  it  is  lined  by  a  thin  vascular  meni- 
brane,and  has  on  its  fore  part  a  groove  or  fissure,which, 
terminating  in  a  sharp  point,  is  named  CALAMUS  SCRIP- 
TORIUS.  On  each  side  of  this  groove  are  seen  several 
medullary  lines,  which  are  the  origin  of  the  portio  mol- 
lis  of  the  seventh  pair  of  nerves.  The  iter  a  tertio  ad 


108  LONDON    DISSECTOR,  OR 

quartum  ventriculum  enters  the  upper  part  of  the  fourth 
ventricle.  The  valvula  cerebri  hangs  over  it. 

On  cutting  the  cerebellum  perpendicularly,  there  is 
formed,  from  the  intermixture  of  cineritious  and  me- 
dullary matter,  a  tree-like  appearance,  named  ARBOR 
VITJE,  of  which  the  trunk  is  termed  the  peduncle  of 
the  cerebellum,  and  is  continued  to  the  back  part  of 
the  medulla  oblongata.  This  concludes  the  demon- 
stration of  the  cerebellum. 

To  demonstrate  the  medulla  oblongata  and  nerves, 
either  the  brain  must  be  removed  from  the  cranium, 
or  it  may  be  gradually  inverted  in  the  progress  of  the 
demonstration; — and  this  is  the  better  method.  The 
inversion  must  be  begun  at  the  fore-part,  by  raising  the 
anterior  lobes  of  the  cerebrum.  Thus  you  will  see, 

1.  The  FIRST  PAIR  OF  NERVES,  the  OLFACTORY, 
called  also  Processus  Mammillares.     They  arise  from 
the  outside  of  the  corpora  striata,  between  the  anterior 
and  middle  lobe  of  the  brain;  run  under  the  anterior 
lobes;  being  lodged  on  two  superficial  grooves,  and 
lying  between  the  pia  and  dura  mater;  expand  into  a 
small  oval  ganglion,  from  which  several  small  filaments 
descend  through  the  cribriform  plate  of  the  ethmoid 
bone,  to  ramify  on  the  membrane  lining  the  nose. 

2.  The  SECOND  PAIR,  the  OPTIC,  arise  from  the 
posterior  part  of  the  optic  thalami,  and  also  from  the 
tubercula  quadrigemina;  they  make  a  circle  round  the 
crura  cerebri  called  the  TRACTUS  OPTICUS.     The  two 
nerves  approach  gradually,  and  unite,  just  before  the 
pituitary  gland,  on  the  fore  part  of  the  sella  Turcica. 
They  then  diverge,  and  each  nerve  passes  out  at  the 
foramen  opticum  of  the  sphenoid  bone,  to  form  the 
retina  of  the  eye. 

On  each  side  of  these  nerves  are  seen  the  CAROTID 
ARTERIES.  Each  artery  emerges  from  the  cavernous 
sinus  by  the  side  of  the  anterior  clinoid  process:  sends 


GUIDE    TO    ANATOMY.  109 

a  branch  forwards,  which,  uniting  with  a  similar  branch 
of  the  other  carotid,  forms  the  anterior  part  of  the  Cm- 
CULUS  ARTERIOSUS  Willisii;  while  other  branches, 
passing  backwards,  and  uniting  with  branches  of  the 
basilar  artery,  complete  the  posterior  part  of  the  arte- 
rial circle. 

A  fold  of  dura  mater  passes  from  the  anterior  to  the 
posterior  clinoid  process  of  each  side.  This  fold  is 
double,  and  forms  by  its  duplicature  the  CAVERNOUS 
SINUS. 

On  dividing  the  optic  nerves,  and  inverting  them, 
we  see  the  infundibulum,  a  funnel  of  cineritious  sub- 
stance, leading  from  the  inferior  and  anterior  extremity 
of  the  third  ventricle  to  the  pituitary  gland;  it  is  gene- 
erally  imperforate  before  it  reaches  the  gland. 

The  PITUITARY  GLAND,  a  reddish  body,  somewhat 
globular,  consisting  of  two  lobes,  is  situated  in  the 
sella  Turcica  of  the  sphenoid  bone,  partly  covered  by 
a  fold  of  dura  mater,  and  attached  to  the  infundibulum. 
The  circular  sinus  is  situated  at  this  point. 

On  detaching  the  cerebrum  from  the  back  part 
of  the  sella  Turcica,  the  tunica  arachnoides  is  very 
evident. 

3.  The  THIRD  PAIR  OF  NERVES,  MOTORES  Ocu- 
LORUM,  arise  from  the  crura  cerebri*,  pass  outwards 
and  forwards  on  the  outer  side  of  the  posterior  clinoid 
process  into  the  cavernous  sinus,  and  run  through  the 
foramen  lacerum  orbitale  superius  to  the  muscles  of 
the  eye. 

Between  these  two  nerves  are  seen  the  two  ver- 
tebral arteries,  ascending  and  uniting,  to  form  the 
basilary  artery. 

*  The  two  crura  pass  obliquely  backwards  and  inwards,  so  as  to  con- 
verge and  meet  in  front  of  the  tuber  annulare;  it  is  from  the  hollow 
formed  by  their  convergence,  and  named  by  Vicq  d'Azyr,  fosse  des 
nerfs  occulo-musculaires ,  that  the  third  pair  arise. 

10 


110  LONDON    DISSECTOR,  OR 

4.  The  FOURTH  PAIR,  TROCHLEARES  or  PATHET- 
ici,  are  very  slender,  and  situated  immediately  under 
the  edge  of  the  tentorium.     This  nerve  arises  from 
the  valvula  cerebri,  comes  out  from  betwixt  the  cere- 
brum and  cerebellum,  passes  by  the  side  of  the  pons 
Varolii,  and,  passing  through  the  cavernous  sinus, 
continues  its  course  through  the   foramen   lacerum 
orbitale   superius,  to   supply  the  obliquus   superior 
muscle  of  the  eye. 

5.  The  FIFTH  PAIR,  TRIGEMINI,  are  much  larger 
than  the  fourth,  and  are  situated  more  outwards  and 
backwards.     Each  of  these  nerves  arises,  by  a  num- 
ber of  filaments,  from  the  anterior  and  lowest  part  of 
the  crus  cerebelli,  where  the  crus  unites  with  the 
pons  Varolii; — it  passes  forwards,  enters  the  cavern- 
ous sinus,  where  it  untwists  itself,  and  forms  a  flat 
irregular  ganglion,  the  GANGLION  GASSERIANUM,  and 
then  divides  into  three  great  branches. 

(1.)  RAMUS  OCULARIS. — The  ophthalmic  nerve  of 
Willis  passes  through  the  foramen  lacerum  orbitale 
superius  to  the  appendages  of  the  eye. 

(2.)  RAMUS  MAXILLARIS  SUPERIOR  passes  through 
the  foramen  rotundum  to  the  upper  jaw  and  face. 

(3.)  RAMUS  MAXILLARIS  INFERIOR  passes  through 
the  foramen  ovale  to  the  lower  jaw  and  tongue. 

6.  The   SIXTH  PAIR,  MOTORES  OCULORUM  Ex- 
TERNI,  or  abductores  vel  abducentes. — This  nerve  is 
small,  but  not  so  small  as  the  fourth  pair;  it  is  seen 
arising  betwixt  the  pons  Varolii  and  corpora  pyrami- 
dalia:  it  enters  the  cavernous  sinus, — it  there  runs  by 
the  side  of  the  carotid  artery,  and  passes  through  the 
foramen  lacerum  orbitale  superius  to  the  rectus  exter- 
nus  oculi. 

While  in  the  cavernous  sinus,  it  gives  off  the  small 
twig,  which,  uniting  with  filaments  from  the  second 
branch  of  the  fifth  pair,  forms  the  beginning  of  the 


GUIDE    TO    ANATOMY.  Ill 

intercostal  nerve,   and  passes  out  of  the   cranium 
through  the  foramen  caroticum  with  the  carotid  artery. 

7.  The  SEVENTH  PAIR,  NERVI  AUDITORII,  con- 
sists of  two  portions. 

(1.)  The  Portio  Dura,  or  the  fascial  nerve,  arises 
from  the  crus  cerebelli,  and  comes  out  from  the  fossa 
or  groove  betwixt  the  pons  Varolii,  corpora  olivaria, 
and  crura  cerebelli. 

(2.)  The  Portio  Mollis,  or  more  properly  the  audi- 
tory nerve,  arises  from  the  inner  surface  of  the  fourth 
ventricle;  it  has  a  groove  on  its  surface  for  receiving 
the  portio  dura; — accompanied  by  an  artery,  they 
enter  the  meatus  auditorius  internus,  where  the  portio 
mollis  is  distributed  to  the  parts  of  the  internal  ear, 
while  the  portio  dura  runs  through  the  aqueduct  of 
Fallopius,  and  conies  out  at  the  stylo-mastoid  foramen 
below  the  ear,  to  form  the  principal  nerve  of  the  face. 

8.  The  EIGHTH  PAIR,  PAR   VAGUM,   arises  by 
numerous   filaments   from  the  sides  of  the  corpora 
olivaria  and  medulla  oblongata.     Two  distinct  fasci- 
culi are  formed,  the  uppermost  called  nervus  glosso- 
pharyngeus,  the  other  the  proper  par  vagum; — they 
unite,  run  towards  the  foramen  lacerum  in  basi  cranii, 
pierce  the  dura  mater,  and  pass  out  through  the  ante- 
rior part  of  that  hole,  having  been  first  joined  by  the 

NERVUS  ACCESSORIUS  AD  PAR  VAGUM,  or  spinal 
accessory,  which  runs  up  from  the  medulla  spinalis 
through  the  great  occipital  foramen.  i 

The  great  LATERAL  SINUS  passes  out  by  the  back- 
part  of  the  same  foramen,  to  form  the  internal  jugular 
vein;  it  is  separated  from  the  nerve  by  a  slip  of 
cartilage. 

9.  The  NINTH  PAIR,  LINGUALES,  Linguales  Medii, 
Hypoglossi. — This    nerve    arises  from  the  furrow 
betwixt  the  corpora  olivaria  and  pyramidalia,  by 
several  filaments  which  often  pierce  the  dura  mater 
separately.     It  passes  through  the  anterior  condyloid 


112  LONDON    DISSECTOR,  OR 

hole  of  the  occipital  bone,  to  supply  the  muscles  of 
the  tongue. 

Immediately  after  leaving  the  cranium,  the  eighth 
and  ninth  pair,  and  the  ganglion  of  the  intercostal, 
are  connected  together. 

10.  The  TENTH  PAIR,*  SUBOCCIPITALES,  arise,  on 
each  side,  by  two  bundles,  from  the  extremity  of  the 
medulla  oblongata,  and  upper  part  of  the  spinal  mar- 
row, pass  through  the  dura  mater  by  the  same  foramen 
which  gives  entrance  to  the  vertebral  artery,  and  run 
through  the  foramen  magnum  occipitale  to  the  muscles 
at  the  base  of  the  cranium. 

The  corpora  albicantia  Willisii,  are  again  seen, 
two  white  bodies,  on  the  base  of  the  brain,  behind 
the  infundibulum,  and  above  the  pons  Varolii. 

The  MEDULLA  OBLONGATA  remains  to  be  demon- 
strated. It  should  be  removed  from  the  bone,  and 
examined  in  an  inverted  position,  On  its  under  surface 
are  seen  the  two  vertebral  arteries,  ascending  from 
the  foramen  magnum,  and  uniting,  to  form  one  trunk, 
the  basilar  artery. 

On  removing  the  pia  mater,  the  whole  surface 
appears  medullary;  but  an  incision  shows  it  to  be 
intermixed  with  the  cineritious  substance. 

The  CRURA  or  PEDUNCULI  CEREBRI  are  two  con- 
siderable medullary  fasciculi,  proceeding  from  the 
centre  of  the  medulla  of  the  brain,  more  immediately 
from  the  corpora  striata;  they  unite  at  an  acute  angle, 
and  are  united  to  the  pons  Varolii.f 

The  CRURA  or  PEDUNCULI  CEREBELLI  are  very 
large,  and  pass  from  the  medullary  part  of  the  cere- 
bellum which  forms  the  arbor  vitae  to  the  pons  Varolii. 

*  These  are  now  perhaps  as  frequently  described  as  the  first  pair  of 
cervical  nerves. 

f  On  making  a  section  of  the  crura  cerebri,  near  to  their  union  with 
the  pons  Varolii,  a  portion  of  a  dark- brown  colour,  surrounded  with 
white  medullary  substance,  is  seen,  termed  Locus  Niger  Crurum 
Cerebri . 


GUIDE    TO    ANATOMY.  113 

The  PONS  VAROLII,  Tuber  Annulare,  or  Nodus 
Cerebri,  is  a  medullary  protuberance,  formed  by  the 
union  of  the  crura  cerebri  and  cerebelli,  over  which 
it  is  stretched  like  a  bridge;  on  its  surface  is  a  raphe, 
or  transverse  fibres  passing  into  a  middle  longitudinal 
narrow  depression. 

Below  the  pons  Varolii,  and  separated  from  it  by  a 
sulcus,  are  seen  four  eminences: 

1.  The  two  external  are  named  CORPORA  OLIVA- 

RIA. 

2.  The  two  internal  are  named  CORPORA  PYRA- 
MIDALIA,  and,  by  separating  these  two  bodies,  medul- 
lary cords,  passing  transversely,  appear,  the  nervi 
intercerebrales. 

Small  cords  also  project  from  the  back  part  of  the 
corpora  olivaria,  which  have  received  the  name  of 
Corpora  Restiformia. 

The  point  of  union  betwixt  the  corpora  pyramidalia 
and  pons  Varolii,  is  sometimes  called  foramen  caecum. 

The  medulla  oblongata  now  contracts  itself,  and 
passing  through  the  foramen  magnum  occipitale, 
assumes  the  name  of 

MEDULLA  SPINALIS,  or  the  Spinal  Marrow.  This 
part  of  the  nervous  or  sensorial  system  must  be  here 
described,  although  its  dissection  cannot  be  performed 
till  all  the  muscles  of  the  back  are  removed,  so  that 
the  posterior  part  of  the  spinal  canal  may  be  sawed 
off. 

The  spinal  canal  is  lined  by  a  strong  ligamentous 
sheath,  and  the  dura  mater  is  continued  down  upon  this 
sheath  in  the  form  of  a  funnel. 

The  spinal  marrow  consists  externally  of  medullary 
substance,  internally  of  cineritious.  It  runs  down  to 
the  first  lumbar  vertebra,  where  it  terminates  by 
numerous  filaments,  which  form  the  cauda  equina.  It 
is  closely  embraced  by  the  pia  mater,  while  the  tunica 
arachnoides  adheres  to  that  membrane  very  loosely. 
10* 


114  LONDON    DISSECTOR,  &C. 

During  the  whole  of  its  passage,  there  is  on  each  side 
a  membranous  connection  betwixt  the  pia  and  dura 
mater,  by  distinct  slips,  irregular  and  pointed,  which 
connection  is  named  LIGAMENTUM  DENTICULATUM. 
The  arteries  of  the  medulla  may  be  seen  running  down 
on  its  anterior  and  posterior  surfaces;  they  are  branches 
of  the  vertebral  artery. 

The  spinal  accessory  nerve  is  seen  arising  by  small 
twigs  from  the  posterior  bundles  of  the  fourth,  fifth, 
sixth,  and  seventh  cervical  nerves;  it  then  ascends 
along  the  spinal  canal,  enters  the  foramen,  and  passes 
forwards,  to  accompany  the  par  vagum. 

The  spinal  marrow  sends  off'  twenty-nine  pair  of 
spinal  nerves,  which  pass  through  the  foramina  formed 
betwixt  the  bodies  of  the  vertebrae.  They  consist  of 
seven  cervical,  twelve  dorsal,  five  lumbar,  and  five 
sacral  pairs  of  nerves.  Each  of  these  nerves  arises 
in  two  fasciculi,  one  from  the  fore  part,  the  other  from 
the  back  part  of  the  spinal  marrow;  these  fasciculi 
penetrate  the  dura  mater  separately;  the  posterior 
bundle  forms  a  ganglion,  and  afterwards  unites  with 
the  anterior  fasciculus,  to  form  the  nerve. 


CHAPTER    VII. 

DISSECTION   OF    THE   ANTERIOR 
PART   OF   THE    NECK. 


THE  utility  of  this  dissection  must  be  evident,  when 
you  consider  how  many  important  parts  are  contained 
in  the  fore  part  of  the  neck.  The  tube  which  conveys 
air  to  the  lungs,  the  vessels  which  are  sent  from  the 
heart  to  the  brain,  and  the  nerves  which  are  destined 
to  supply  the  thoracic  and  abdominal  viscera,  are  here 
situated,  and  all  these  parts  lie  imbedded  in  cellular 
substance;  hence  the  dissection  is  intricate,and  requires 
the  utmost  care  in  its  performance. 

The  muscles  of  the  anterior  part  of  the  neck,  are 
sixteen  in  number  on  each  side.  They  may  be  divided 
into  muscles  situated  superficially,  muscles  at  the  upper 
part  of  the  neck,  and  those  situated  at  the  lower  part. 

The  superficial  muscles  are  two:  to  display  thei% 
make  an  incision  from  the  chin  to  the  sternum,  another 
along  the  clavicle,  and  a  third  along  the  edge  of  the 
inferior  maxillary  bone;  dissect  up  the  flap  and  you  will 
expose  immediately  under  the  integuments,  and  adher- 
ing to  them, 

1.  The  Museums  CUTANEUS,  vulgo,  Platysma 
myoides,  or  Latissimus  Colli. — It  arises,  by  slender 
separate  fleshy  fibres,  from  the  cellular  substance, 
covering  the  upper  part  of  the  deltoid  and  pectoral 
muscles.  These  fibres  form  a  thin  broad  muscle, 
which  runs  obliquely  upwards,  and  is 

Inserted  into  the  skin  and  muscles  covering  the  lower 
jaw  and  cheek. 


116  LONDON    DISSECTOR,  OR 

Use:  To  draw  the  skin  of  the  cheek  downwards, 
and,  when  the  mouth  is  shut,  to  draw  the  skin  under 
the  lower  jaw  upwards:  others  say  that  it  assists  the 
respiration  and  circulation. 

Remove  the  platysma  myoides  from  its  origin,  and 
invert  it  over  the  face.  Immediately  beneath  it  is  seen 
the  external  jugular  vein,  which  is  formed  of  branches 
from  the  temple,  side  of  the  face,  and  throat.  It  crosses 
obliquely  over  the  sterno-mastoideus,  passes  behind 
the  outer  edge  of  that  muscle,  and  dives  beneath  the 
clavicle,  to  enter  the  subclavian  vein. 

2.  The  STERNO-CLEIDO-MASTOIDEUS — Arises,  by 
two  distinct  origins;  the  anterior,  tendinous  and  fleshy, 
and  somewhat  round,  from  the  top  of  the  sternum,  near 
its  junction  with  the  clavicle;  the  posterior  or  outer, 
fleshy  and  flat,  from  the  upper  and  anterior  part  of  the 
clavicle.  These  two  origins  soon  unite,  and  form  a 
strong  muscle,  which  ascends  obliquely  upwards  and 
outwards,  to  be 

Inserted,  tendinous,  into  the  outside  of  the  mastoid 
process,  and  into  the  transverse  ridge  behind  that  pro- 
cess. 

Use:  When  one  acts  singly,  it  turns  the  head  to  one 
side.  When  both  act  together,  they  bend  the  head 
forwards. 

The  muscle  should  be  detached  from  the  sternum 
and  clavicle,  and  left  suspended  by  its  insertion.  It  is 
pierced  by  several  branches  of  the  cervical  nerves,  and 
about  its  middle,  it  is  perforated  by  the  Nervus  Ac- 
cessorius.  These  nerves  ramify  on  the  neighboring 
muscles  of  the  neck  and  shoulder.  Between  the  pos- 
terior edge  of  the  sterno-cleido-mastoideus  and  the 
fore  part  of  the  trapezius  muscles,  is  seen  a  quantity 
of  loose  fatty  substance,  intermixed  with  branches  of 
nerves.  This  fatty  substance  is  watery  and  granu- 
lated; it  must  not  be  removed  roughly,  lest  important 


GUIDE    TO    ANATOMY.  117 

nerves  and  vessels  be  injured;  it  is  continued  around 
the  vessels  under  the  clavicle. 

In  the  middle  of  the  throat  may  be  seen: 

The  Os  Hyoides,  or  bone  of  the  tongue,  forming  the 
uppermost  of  the  projections  beneath  the  chin. 

The  Larynx,  or  upper  part  of  the  trachea,  consist- 
ing of  five  cartilages,  of  which  two  are  evident  exter- 
nally, viz:  the  uppermost  and  largest  the  thyroid  car- 
tilage; and  the  inferior  or  cricoid  cartilage.  The  two 
arytenoid  cartilages,  and  the  epiglottis,  lie  behind  this. 

The  Trachea,  consisting  of  cartilaginous  rings, 
and  extending  into  the  thorax. 

Behind  the  larynx  is  situated  the  pharynx.  At  the 
part  where  the  larynx  terminates  in  the  trachea,  the 
pharynx  contracts  itself,  and  forms  the  oesophagus,  or 
muscular  tube,  conveying  the  food  to  the  stomach, 
which  descends  behind  the  trachea,  situated  rather  to 
the  left  side  of  the  cervical  vertebrae. 

These  parts  are  covered  by  muscles,  and  on  each 
side  of  the  trachea  lie  the  great  vessels  and  nerves. 

The  muscles  at  the  lower  part  of  the  neck  are 
five. 

3.  The     STERNO-HYOIDEUS — Arises,    thin    and 
fleshy,  from  the  upper  and  inner  part  of  the  sternum, 
clavicle,  and  first  rib: — It  forms  a  flat  narrow  muscle. 

Inserted  into  the  base  of  the  os  hyoides. 

This  pair  of  muscles  is  seen  on  removing  the 
platysma  myoides,  between  the  sterno-cleido  mas- 
toidei. 

Use:  To  pull  the  os  hyoides  downwards. 

4.  The  OMO-HYOIDEUS — Arises,  broad,  thin,  and 
fleshy,  from  the  root  of  the  coracoid   process,  and 
semilunar  notch  of  the  scapula,  ascends  across  the 
neck,  and  forms  a  middle  tendon,  where  it  passes 
below  the  sterno-cleido-mastoideus.    Becoming  fleshy 
again,  it  runs  up,  and  is 


118  LONDON    DISSECTOR,  OR 

Inserted  into  the  base  of  the  os  hyoides,  between  its 
cornu  and  the  insertion  of  the  sterno-hyoideus. 

The  lower  part  of  this  muscle  is  covered  by  the 
trapezius;  its  middle  by  the  sterno-cleido-mastoideus; 
its  anterior  part  is  seen  on  removing  the  platysma 
myoides;  it  crosses  over  the  carotid  artery,  and  internal 
jugular  vein. 

Use:  To  assist  in  drawing  down  the  os  hyoides. 

On  dividing  the  sterno-hyoideus,  observe  under  it, 

5.  The  STERNO  THYROIDEUS. — This  muscle  arises, 
fleshy,  from  the  inside  of  the  sternum,  and  of  the 
extremity  of  the  first  rib;  forms  a  flat  muscle,  and  is 

Inserted  into  the  inferior  edge  of  the  thyroid  car- 
tilage. 

Use:  To  draw  the  thyroid  cartilage,  and  conse- 
quently the  larynx,  downwards. 

Under  the  sterno-thyroideus,  we  find  situated  the 

THYROID  GLAND,  a  large  reddish  mass,  situated  on 
the  superior  rings  of  the  trachea,  below  the  cricoid 
cartilage;  in  form  somewhat  like  a  crescent,  with  the 
cornua  turned  upwards. 

6.  The  THYRO-HYOIDEUS — Arises,   fleshy,  from 
the  upper  surface  of  the  oblique  ridge  in  the  ala  of 
the  thyroid  cartilage,  and  passes  upwards,  to  be 

Inserted  into  part  of  the  base,  and  almost  all  the 
cornu  of  the  os  hyoides.  It  is  covered  by  the  sterno- 
hyoideus. 

7.  The  CRICO-THYROIDEUS — Jlrises,  tendinous  and 
fleshy,  from  the  side  and  fore  part  of  the  cricoid 
cartilage,  and  runs  obliquely  upwards. 

Inserted,  by  two  fleshy  portions,  the  first  into  the 
lower  part  of  the  thyroid  cartilage,  and  the  second 
into  its  inferior  cornu. 

It  is  found  on  the  side  of  the  larynx,  and  under  the 
sterno-thyroideus,  and  serves  to  pull  forwards  and 
depress  the  thyroid,  or  to  elevate  and  draw  backwards 
the  cricoid  cartilage. 


GUIDE    TO    ANATOMY.  119 

The  muscles  at  the  upper  part  of  the  neck  consist 
of  nine  pair. 

8.  The  DIGASTRICUS — Arises,  from  the  fossa  at  the 
root  of  the  mastoid  process  of  the  temporal  bone;  its 
fleshy  belly  terminates   in   a   strong  round   tendon, 
which  runs  downwards  and  forwards,  passes  through 
the  fleshy  belly  of  the  stylo-hyoideus,  is  fixed  by 
strong  ligamentous  and  tendinous  fibres  to  the  os 
hyoides,  from  which  it  receives  an  addition  of  fibres; 
it  then  becomes   again  fleshy,   and  runs  obliquely 
upwards,  to  be 

Inserted  into  a  rough  sinuosity  on  the  lower  jaw 
behind  the  Chin. 

Its  posterior  belly  is  covered  by  the  sterno-cleido- 
mastoideus;  but  its  anterior  lies  immediately  under 
the  skin  and  platysma  myoides. 

Use:  To  open  the  mouth,  by  pulling  the  lower  jaw 
downwards  and  backwards;  and,  when  the  jaws  are 
shut,  to  raise  the  larynx,  and  consequently  the  pharynx, 
in  deglutition. 

In  the  triangular  space  formed  by  the  two  bellies  of 
this  muscle,  and  the  base  of  the  lower  jaw,  lies  the 
SuBivtAxiLLARY  GLAND.  It  rests  upon  a  flat  muscle, 
the  mylo-hyoideus,  which  is  seen  between  the  two 
bellies  of  the  digastric  us;  the  gland  is  surrounded  by 
little  absorbent  glands. 

9.  The  STYLO-HYOIDEUS — Arises,  tendinous,  from 
the  middle  and  inferior  part  of  the  styloid  process  of 
the  temporal  bone;  its  fleshy  belly  is  generally  perfo- 
rated by  the  digastricus. 

Inserted^  tendinous,  into  the  os  hyoides  at  the  junc- 
ture of  its  base  and  cornu. 

The  origin  of  this  muscle  is  situated  more  inwards 

than  the  last,  and  nearer  the  base  of  the  cranium;  it  is 

the  most  superficial  of  three  muscles  which  arise  from 

the  styloid  process;  sometimes  it  is  accompanied  by 

• 


120  LONDON    DISSECTOR,  OR 

another  small  muscle,  having  the  same  origin  and 
insertion,  the  stylo-hyoideus  alter. 

Use:  To  pull  the  os  hyoides  to  one  side,  and  a  little 
upwards. 

10.  The   STYLO-GLOSSUS — Jlrises,   tendinous  and 
fleshy,  from  the  styloid  process,  and  from  a  ligament 
that  connects  that  process  to  the  angle  of  the  lower 
jaw.      It  descends,  and  becomes  broader,  but  less 
thick. 

Inserted  into  the  root  of  the  tongue,  runs  along  its 
side,  and  is  insensibly  lost  near  its  tip. 

Use:  To  move  the  tongue  laterally  and  backwards. 

1 1 .  The  STYLO-PHARYNGEUS — Arises,  fleshy,  from 
the  root  and  inner  part  of  the  styloid  process. 

Inserted  into  the  side  of  the  pharynx  and  back  part 
of  the  thyroid  cartilage. 

It  is  situated  deeper,  and  behind  the  stylo-glossus, 
and  serves  to  dilate  and  raise  the  pharynx  and  thyroid 
cartilage  upwards. 

On  removing  the  submaxillary  glands,  and  detaching 
the  digastric  muscle  from  the  os  hyoides  and  chin,  we 
expose  the  next  muscle. 

12.  The  MYLO-HYOIDEUS — Arises,  fleshy,  from  all 
the  inside  of  the  lower  jaw,  between  the  last  dens 
molaris  and  the  middle  of  the  chin;  the  fibres  form  a 
flat  muscle,  converge,  and  are 

Inserted  into  the  lower  edge  of  the  base  of  the  os 
hyoides;  it  unites  with  its  fellow  in  a  middle  tendi- 
nous line  which  extends  from  the  os  hyoides  to  the 
chin;  its  posterior  part  is  lined  by  the  internal  mem- 
brane of  the  mouth;  it  lies  under  the  digastricus,  but 
is  seen  betwixt  its  bellies. 

Use:  To  pull  the  os  hyoides  forwards,  upwards,  and 
to  either  side. 

The  submaxillary  gland  sends  off  a  duct,  which 
passes  behind  the  posterior  edge  of  the  mylo-hyoideus, 
then  runs  along  the  inner  surface  of  this  muscle  for- 


GUIDE    TO    ANATOMY.  121 

wards  and  upwards,  on  the  inside  of  the  sublingual 
gland  to  open  into  the  mouth  on  the  side  of  the  frenum 
of  the  tongue. 

The  SUBLINGUAL  GLAND  lies  immediately  above 
the  mylo-hyoideus,  betwixt  it  and  the  internal  mem- 
brane of  the  mouth,  where  it  lines  the  side  and  inferior 
surface  of  the  tongue.  It  sends  off  several  ducts, 
which  open  into  the  mouth  between  the  root  of  the 
tongue  and  side  of  the  lower  jaw. 

The  removal  of  the  mylo-hyoideus  exposes  a  pair 
of  muscles,  which  are  closely  attached  to  one  another. 

13.  The  GENIO-HYOIDEUS — Arises,  tendinous,  from 
a  projection  on  the  inside  of  that  part  of  the  lower  jaw 
which  is  called  the   Chin;   it  descends,  becoming 
broader,  and  is 

Inserted  into  the  basis  of  the  os  hyoides. 

Use:  To  draw  the  os  hyoides  forwards  and  upwards 
to  the  chin. 

By  removing  this  muscle,  or  turning  it  back  from 
its  origin  from  the  jaw,  we  discover  the  next  muscle. 

14.  The  GENIO-HYO-GLOSSUS — Arises,  tendinous, 
from  a  rough  protuberance  on  the  inside  of  the  lower 
jaw,  higher  up  than  the  origin  of  the  genio-hyoideus; 
its  fibres  run  forwards,  upwards,  and  backwards,  in  a 
very  wide  and  radiated  manner,  to  be 

Inserted,  some  into  the  posterior  part  of  the  base  of 
the  os  hyoides,  near  its  cornu,  others  into  the  tip, 
middle,  and  root  of  the  tongue. 

This  muscle  lies  under  the  genio-hyoideus  before; 
and  more  outwardly,  under  the  mylo-hyoideus. 

Use:  According  to  the  direction  of  its  fibres,  to  draw 
the  tip  of  the  tongue  backwards  into  the  mouth,  the 
middle  downwards,  and  to  render  its  dorsum  concave; 
to  draw  its  root  and  the  os  hyoides  forwards,  and  to 
thrust  the  tongue  out  of  the  mouth. 

It  is  called  also  Genio-glossus. 

15.  The  HYO-GLOSSUS — Arises •,  broad  and  fleshy, 

11 


122  LONDON    DISSECTOR,  OR 

from  half  of  the  base,  and  part  of  the  cornu  of  the  os 
hyoides;  the  fibres  run  upwards,  to  be 

Inserted  into  the  side  of  the  tongue. 

It  is  situated  more  outwardly  than  the  genio-hyo- 
glossus,  and,  at  its  insertion  into  the  tongue,  mixes 
with  the  stylo-glossus. 

It  moves  the  tongue  inwards  and  downwards. 

16.  The  LINGUALIS — Arises  from  the  root  of  the 
tongue  laterally,  and  runs  forwards  between  the  hyo- 
glossus  and  genio-hyo-glossus,  to  be 

Inserted  into  the  tip  of  the  tongue,  along  with  part 
of  the  stylo-glossus. 

Use:  To  contract  the  substance  of  the  tongue,  and 
bring  it  backwards. 


CHAPTER    VIII. 

DISSECTION    OF    THE   MUSCLES   ON 
THE  OUTSIDE  OF  THE  THORAX. 

IN  removing  the  integuments  from  the  fore  part  of 
the  thorax,  the  pectoralis  major  and  interior  edge  of 
the  deltoid  muscle  should  be  dissected  in  the  course  of 
their  fibres;  and  to  do  this,  it  will  be  necessary  to 
remember  that  the  fibres  run  obliquely  from  the  ster- 
num and  clavicle  to  the  upper  part  of  the  os  humeri. 
They  are  not  covered  by  any  fascia,  but  by  a  con- 
densed cellular  membrane. 

Three  pair  of  muscles  are  described  in  this  dissec- 
tion. 

1.  The  PECTORALIS  MAJOR — Arises,  tendinous, 
from  the  anterior  surface  of  the  sternum,  its  whole 


GUIDE    TO    ANATOMY.  123 

length;  fleshy,  from  the  cartilages  of  the  fifth,  sixth, 
and  sometimes  the  seventh  ribs,  and  from  two  anterior 
thirds  of  the  clavicle.  The  fleshy  fibres  run  obliquely 
across  the  breast,  and,  converging,  form  a  strong  flat 
tendon,  which  is 

Inserted  into  the  outside  of  the  bicipital  groove  of 
the  os  humeri. 

The  clavicular  and  thoracic  portions  of  the  muscle 
are  separated  by  a  line  of  cellular  membrane.  The 
tendon  is  covered  by  the  anterior  edge  of  the  deltoid; 
it  forms  the  anterior  fold  of  the  arm-pit,  and  appears 
twisted;  for  the  fibres,  which  proceed  from  the  tho- 
racic portion  of  the  muscle,  seem  to  pass  behind  those 
proceeding  from  the  clavicle,  and  to  be  inserted  into 
the  os  humeri  somewhat  higher  up. 

Use:  to  move  the  arm  forwards,  and  obliquely 
upwards,  towards  the  sternum;  or  to  draw  it  towards 
the  side. 

The  pectoralis  major  should  be  lifted  up  from  its 
origin,  and  suspended  by  its  tendon.  This  will  expose 
the  next  two  muscles. 

2.  The  PECTORALIS  MINOR — Arises,  by  three  ten- 
dinous and  fleshy  digitations,  from  the  upper  edges  of 
the  third,  fourth,  and  fifth  ribs,  near  their  cartilages;  it 
forms  a  fleshy  triangular  belly  which  becomes  thicker 
and  narrower  as  it  ascends,  and  is 

Inserted,  by  a  short  flat  tendon,  into  the  anterior 
part  of  the  coracoid  process  of  the  scapula. 

The  belly  of  this  muscle  is  covered  by  the  pecto- 
ralis major;  the  tendon  passes  under  the  anterior  edge 
of  the  deltoid,  and  is  connected  at  its  insertion  with 
the  origins  of  the  coraco-brachialis,  and  of  the  short 
head  of  the  biceps  flexor  cubiti,  and  also  -with  the 
ligamentum  proprium  scapulae  anticum,  a  strong  liga- 
ment, which  passes  from  the  external  edge  of  the 
coracoid  process,  to  be  affixed  to  the  posterior  margin 
of  the  acromion  of  the  scapula, 


124  LONDON    DISSECTOR,  OR 

Use:  To  draw  the  scapula  forwards  and  down- 
wards, and,  when  that  bone  is  fixed,  to  elevate  the 
ribs. 

This  muscle  is  called  also  Serratus  minor  anticus. 

3.  The  SUBCLAVIUS — Arises ,  by  a  flat  tendon,  from 
the  cartilage  of  the  first  rib,  and  forms  a  broad  fleshy 
belly,  which  is 

Inserted  into  the  inferior  surface  of  the  clavicle, 
beginning  about  one  inch  from  the  sternum,  and  con- 
tinuing as  far  as  the  ligamentous  connection  of  the 
clavicle  to  the  coracoid  process. 

This  muscle  is  situated  between  the  clavicle  and 
sternum,  and  is  concealed  by  the  pectoralis  major,  and 
the  anterior  part  of  the  deltoid.  » 

Use:  to  draw  the  clavicle  downwards  and  forwards, 
and  perhaps  to  elevate  the  first  rib. 

Having  lifted  up  the  pectoralis  minor  from  its  origin, 
the  situation  of  the  subclavian  vessels  which  pass  under 
the  clavicle,  and  over  the  first  rib,  may  be  seen. 

OF   THE    PARTS   WITHIN   THE    THORAX. 

The  cavity  of  the  thorax  may  now  be  opened,  by 
cutting  through  the  cartilages  of  the  ribs  on  each  side, 
and  separating  the  lower  part  of  the  sternum  from  the 
diaphragm.  That  bone  must  then  be  lifted  upwards 
and  removed,  by  separating  it  at  its  articulations  with 
the  clavicle.  This  will  allow  us  to  examine  more 
readily  the  great  vessels  passing  out  of  the  thorax. 

On  looking  under  the  sternum,  while  it  is  lifted  up, 
we  see  the  Mediastinum,  separating,  as  it  is  gradually 
torn  from  the  posterior  surface  of  the  sternum,  into  two 
layers,  and  thus  forming  a  triangular  cavity.  This 
cavity  is  artificially  produced,  and  is  entirely  owing  to 
the  method  of  raising  the  sternum. 

When  the  sternum  is  laid  back  or  removed,  the  fol- 
lowing parts  are  to  be  observed: 


TO    ANATOMY.  125 

The  MEDIASTINUM,  now  collapsed,  dividing  the 
thorax  into  two  distinct  cavities,  of  which  the  right  is 
the  largest. 

The  lungs  of  each  side  lying  distinct  in  these 
cavities. 

The  Pericardium,  containing  the  heart,  situated  in 
the  middle  of  the  thorax,  between  the  two  laminae  of 
the  mediastinum,  and  protruding  into  the  left  side. 

The  internal  surface  of  the  pleura,  smooth,  colorless, 
and  glistening,  lining  the  ribs,  and  reflected  over  the 
lungs. 

1 .  The  PLEURA. — Each  side  of  the  thorax  has  its 
particular  pleura. — The  pleurae  are  like  two  bladders, 
situated  laterally  with  respect  to  each  other;  by  ad- 
hering together  in  the  middle  of  the  thorax,  and  pass- 
ing obliquely  *  from  the  posterior  surface  of  the  ster- 
num to  the  dorsal  vertebrae,  they  form  the  mediasti- 
num.— The  pleura  lines  the  ribs,  and  the  upper  surface 
of  the  diaphragm,  and  is  reflected  over  the  lung,  which 
is  in  fact  behind  it;  it  forms  the  ligamentum  latum  pul- 
monis,  a  reflection  of  this  membrane,  which  connects 
the  inferior  edge  of  the  lungs  to  the  spine  and  dia- 
phragm. 

2.  The  LUNGS. — Reddish  in  children,  greyish  in 
adults,  and  blue  in  old  age.   Their  shape  corresponds  to 
that  of  the  thorax,  being  pyramidal,  convex  towards 
the  ribs,  concave  towards  the  diaphragm,  and  irregu- 
larly flattened  next  the  mediastinum. 

The  Right  Lung  is  the  larger,  and  is  divided  into 
three  lobes,  two  large  ones,  and  an  intermediate  smaller 
lobe. 

The  Left  Lung  has  two  lobes,  and  also  a  square  notch 
opposite  the  apex  of  the  heart.  Into  the  sulci  or 

*  They  run  obliquely,  not  being  in  general  attached  to  the  middle  of 
the  sternum,  but  towards  its  left  side,  especially  at  the  lower  part  of  the 
bone,  near  the  diaphragm.  Besides  the  pericardium,  the  mediastinum  con- 
tains betwixt  its  laminae  some  adipose  membrane  and  absorbent  glands. 

11* 


126  LONDON    DISSECTOR,  OR 

grooves  which  form  the  divisions  of  the  lungs  into 
lobes,  the  pleura  enters;  that  part  of  the  lung  which  is 
affixed  to  the  spine,  is  called  its  root;  through  it  the 
great  vessels  enter. 

3.  The  PERICARDIUM  is  a  strong,  white,  and  com- 
pact membrane,  smooth  and  lubricated  upon  the  inside, 
forming  a  bag  for  containing  the  heart,  and  having  its 
inner  lamina  reflected  over  the  substance  of  the  heart 
itself. 

4.  When  you  slit  open  the  fore  part  of  the  pericar- 
dium, you  expose  the  HEART.      The  right  ventricle 
protrudes;  the  right  auricle  also  is  towards  you;  while 
the  left  auricle  is  concealed,  and  only  its  tip  is  seen 
lapping  round  upon  the  left  ventricle.      From  under 
this  tip  of  the  left  auricle,  a  branch  of  the  coronary 
vein,  and  of  the  coronary  artery,  ramify  towards  the 
apex  of  the  heart,  marking  the  situation  of  the  septum 
cordis.     The  left  ventricle  will  be  found  firm,  fleshy, 
and  resisting,  whilst  the  right  ventricle  is  more  loose, 
and  seems  partly  wrapt  round  the  other. 

The  heart  is  situated  obliquely  in  the  middle  of  the 
breast;  its  posterior  surface  is  flat,  and  lies  upon  the 
diaphragm;  its  apex  is  turned  forwards,  and  towards 
the  left  side,  so  that,  in  the  living  body,  it  is  felt  striking 
between  the  fifth  and  sixth  ribs,  at  the  point  where  the 
cartilages  and  bony  extremities  are  united .  The  VENA 
CAVA  SUPERIOR  is  seen  coming  down  from  the  upper 
angle  of  the  pericardium.  The  INFERIOR  CAVA  is  seen 
coming  up  through  the  diaphragm;  but  only  a  very  small 
part  of  this  vein  is  covered  by  the  pericardium;  the  two 
veins  enter  the  right  auricle.  The  RIGHT  AURICLE  is 
turned  forwards,  and  might  be  called  the  anterior;  it 
generally  appears  black,from  the  blood  shining  through 
its  thin  coats.  The  RIGHT  VENTRICLE  is  situated 
almost  directly  opposite.  The  PULMONARY  ARTERY 
arises  from  the  right  ventricle;  its  root  is  concealed 
by  the  right  auricle;  it  ascends  on  the  left  side  of  the 


GUIDE    TO    ANATOMY.  127 

fiiorta,  and  divides  into  the  right  and  left  pulmonary 
arteries:  the  right  passes  under  the  arch  of  the  aorta, 
crosses  behind  it  and  the  vena  cava  superior  to  the 
right  lung,  and  is  the  longer,  whilst  the  left  pulmonary 
artery  passes  to  the  left  lung,  crossing  the  descending 
aorta  anteriorly.  The  PULMONARY  VEINS  enter  the 
left  auricle,  two  veins  come  from  each  lung;  the  right 
veins  are  longer,  because  they  pass  behind  the  vena 
cava  superior.  The  left  auricle  is  situated  on  the  left 
side  of  the  right  auricle,  and  somewhat  behind  it;  its 
tip  is  seen  lapping  round  upon  the  LEFT  VENTRICLE; 
this  is  situated  behind  and  on  the  left  side  of  the  right 
ventricle;  its  substance  is  stronger  and  more  firm  to  the 
touch.  The  AORTA  arises  from  the  back  part  and 
right  side  of  the  left  ventricle;  its  root  is  covered  by 
the  pulmonary  artery;  it  then  ascends  betwixt  that  ar- 
tery and  the  vena  cava  superior.  Immmediately  from 
the  root  of  the  aorta,  within  the  pericardium,  the  two 
coronary  arteries  are  sent  off  to  supply  the  heart  itself. 

As  the  VENA  CAVA  SUPERIOR  descends  before  the 
root  of  the  lungs,  and  on  the  right  side  of  the  aorta, 
immediately  before  it  perforates  the  pericardium,  it 
is  joined  upon  its  posterior  part  by  the  vena  azygos, 
which  comes  forwards  from  the  spine,  returning  the 
blood  from  the  intercostal  spaces. 

Behind  the  sternum,  and  just  above  the  arch  of  the 
aorta,  the  superior  cava  is  seen  receiving  two  great 
branches: 

One  from  the  right  side,  formed  by  the  right  subcla- 
vian  vein,  and  the  right  internal  jugular;  and  another, 
which  is  larger,  from  the  left  side;  formed  by  the  left 
subclavian  and  the  left  internal  jugular.  This  trunk 
crossing  in  front  of  the  arteries  arising  from  the  arch 
of  the  aorta,  enters  the  superior  vena  cava.  Into  the 
posterior  part  of  the  angle  formed  by  the  union  of  the 
left  subclavian  and  the  left  jugular,  the  thoracic  duct 
empties  itself. 


12S  LONDON    DISSECTOR,  OR 

On  each  side  of  the  neck,  the  internal  jugular  vein 
will  be  seen  descending  by  the  side  of  the  carotid, 
while  the  subclavian  vein  comes  from  the  arm. 

The  VENA  C AVA  INFERIOR,  immediately  after  pass- 
ing through  the  diaphragm  from  the  abdomen,  enters 
the  pericardium. 

The  AORTA  leaves  the  heart  opposite  the  fourth 
dorsal  vertebra;  it  crosses  over  the  pulmonary  artery, 
ascends  obliquely  upwards,  backwards,  and  to  the 
right  side,  as  high  as  the  second  dorsal  vertebra.  Here 
it  forms  an  ARCH  or  incurvation,  which  passes  from  the 
right  to  the  left  side,  and  at  the  same  time  obliquely 
from  before  backwards;  it  then  comes  in  contact  with 
the  upper  part  of  the  third  dorsal  vertebra,  and  de- 
scends along  the  spine  in  the  posterior  mediastinum. 
This  arch  of  the  aorta  is  situated  behind  the  first  bone 
of  the  sternum,  behind  and  somewhat  below  the  left 
branch  of  the  vena  cava  superior. 

From  the  upper  part  of  the  arch  come  off  three 
large  arteries: 

The  ARTERIA  INNOMINATA,  or  common  trunk 
of  the  right  carotid  and  subclavian;  the  LEFT  CAROTID 
and  the  LEFT  SUBCLAVIAN. 

The  student  should  observe  also  the  THYMUS  gland; 
a  soft  glandular  body,  lying  before  the  lower  part  of 
the  trachea  and  the  great  vessels  of  the  heart,  a  little 
higher  than  the  tops  of  the  two  pleurae.  It  is  very 
large  in  the  foetus,  smaller  in  adults,  and  nearly  disap- 
pears in  the  aged. 

Where  the  aorta  begins  to  descend,  it  is  connected 
to  the  pulmonary  artery  by  a  ligament,  which,  in  the 
foetus,  was  a  large  canal,  the  DUCTUS  ARTERIOSUS. 

The  heart  may  be  now  removed. 

DISSECTION    OF   THE    HEART,   WHEN    REMOVED    FROM 
THE   BODY. 

The  heart  consists  of  three  tunics  or  coats.  1 .  An 
external  smooth  one,  which  is  a  reflection  of  the  inter- 


GUIDE    TO    ANATOMY.  129 

nal  lamina  of  the  pericardium.  2.  A  middle  muscular 
coat.  3.  A  smooth  internal  coat,  which  is  a  continua- 
tion of  the  internal  coat  of  the  great  veins  and  arteries. 
In  the  right  side  of  the  heart  we  always  meet  with  a 
considerable  quantity  of  coagulated  blood.  In  the  left 
side  there  is  much  less. 

Slit  open  with  the  scissors  the  two  venae  cavae  on 
their  fore  part;  the  inner  surface  of  these  veins,  and  of  the 
right  auricle,  will  be  seen  lined  by  a  smooth  membrane; 
and  in  the  auricle,  the  musculi  pectinati,  or  bundles  of 
muscular  fibres,  will  be  seen  projecting.  At  the  point 
of  union  between  the  two  cavae,  there  is  a  projection 
formed  by  the  thickening  of  the  muscular  coat,  called 
the  TUBERCULUM  LOWERI.  The  SEPTUM  AURICU- 
LARUM  is  seen  separating  the  right  from  the  left  auri- 
cle;— observe  that  it  is  thin,  that  in  it  there  is  an  oval 
depression,  named  FOSSA  OVALIS.  Round  this  fossa 
the  fibres  are  thicker,  forming  the  annulus  ovalis;  this 
is  the  remains  of  the  FORAMEN  OVALE  of  thefoatus;  and 
in  many  adult  subjects  a  probe  may  be  passed  through 
the  superior  part  of  the  fossa  obliquely  into  the  left  au- 
ricle. The  VALVULA  NOBILIS,  or  Eustachian  Valve, 
is  a  membrane-like  duplicature  of  the  inner  coat  of 
the  auricle,  observed  where  the  vena  cava  inferior  is 
continued  into  the  auricle,  and  stretching  from  that  vein 
towards  the  opening  into  the  right  ventricle.  This 
valve  is  sometimes  found  reticulated.  Behind  this  valve 
is  the  orifice  of  the  CORONARY  VEIN,  with  its  small 
valve. 

The  foramina  Thebesii  are  minute  orifices  of  veins, 
which  open  into  all  the  cavities  of  the  heart;  they  are 
most  numerous,  however,  in  the  right  auricle. 

The  OSTIUM  VENOSUM,  or  opening  of  the  right  au- 
ricle into  the  right  ventricle,  is  somewhat  oval;  it  has 
a  valve  which  projects  into  the  right  ventricle. 

The  RIGHT  VENTRICLE  may  now  be  opened  by  an 
incision,  carried  from  the  root  of  the  pulmonary  artery 


130  LONDON    DISSECTOR,  OR 

down  to  the  apex  of  the  heart.  This  incision  should 
be  made  with  care,  lest  the  parts  on  the  inside  of  the 
ventricle  be  destroyed  by  it;  it  should  pass  along  the 
right  side  of  the  septum  ventrieulorum,  the  situation  of 
which  is  marked  out  by  large  branches  of  the  coronary 
artery  and  vein.  A  small  opening  should  first  be  made, 
into  which  one  blade  of  the  scissors  can  be  introduced: 
the  incision  may  be  continued  through  the  apex  of  the 
heart,  or  a  flap  may  be  made  by  another  cut,  passing 
from  the  beginning  of  the  first  along  the  margin  of  the 
right  auricle.  In  this  ventricle,  observe  the  project- 
ing bundles  of  muscular  fibres,  the  TRICUSPID  VALVES 
arising  from  the  margin  of  the  ostium  venosum,  and 
projecting  into  the  right  ventricle.  This  valve  forms  a 
complete  circle  at  its  base,  but  has  its  edge  divided 
into  three  parts,  which  are  attached  by  tendinous  fila- 
ments, named  CHORDAE  TENDING,  to  the  COLUMNS 
CARNEY,  or  muscular  bundles  of  the  ventricle. 

The  SEPTUM  VENTRICULORUM,  or  partition  of  the 
two  ventricles,  is  marked  out  externally  by  two  veins 
running  from  the  apex  to  the  basis  of  the  heart. 

Slit  up  the  pulmonary  artery:  observe  how  it  arises 
from  the  back  part  of  the  right  ventricle,  how  smooth 
the  inside  of  the  ventricle  becomes  as  it  approaches 
the  entrance  of  the  artery,  or  ostium  arteriosum.  Ob- 
serve the  three  SEMILUNAR  or  Sigmoid  VALVES. 
Their  bases  arise  from  the  artery,  their  loose  edges 
project  into  its  cavity,  and  in  the  middle  of  the  loose 
edge  of  each  valve  is  seen  a  small  white  body,  termed 
CORPUS  SESAMOIDEUM  Aurantii.  The  artery  is  seen 
bifurcating  into  the  right  and  left  pulmonary  arteries, 
and,  just  before*  its  bifurcation,  sending  off  to  the  aorta 
the  ductus  arteriosus,  which  in  the  adult  is  a  ligament. 

The  LEFT  AURICLE  has  four  pulmonary  veins 
opening  into  its  cavity,  which  may  be  exposed  by  slit- 
ting up  two  of  these  veins.  Observe  that  its  coats  are 
thicker  than  those  of  the  right  auricle.  The  septum 


GUIDE   TO    ANATOMY.  131 

auricularum,  with  the  fossa  ovalis,  is  here  seen  less 
distinctly  than  on  the  right  side.  Observe  also  the 
ostium  venosum,  opening  into  the  left  ventricle,  and 
giving  attachment  to  the  VALVULA  MITRALIS. 

The  LEFT  VENTRICLE  may  be  opened  in  the  same 
manner  as  the  right,  by  an  incision  carefully  made  in 
the  left  side  of  the  septum  or  partition  of  the  ventricles, 
and  continued  round  the  upper  part  of  the  ventricle, 
under  the  auricle.  Observe  the  great  thickness  of  the 
muscular  coat;  the  VALVULA  MITRALIS,  forming  two 
projections,  which  are  attached  by  the  chordae  tendi- 
neae  to  the  fleshy  columns  of  this  ventricle. 

Slit  up  the  aorta;  it  has  three  semilunar  valves,  which 
resemble  those  of  the  pulmonary  artery: — behind  these 
valves  the  artery  bulges  out,  forming  the  SINUSES  of 
the  aorta.  Above  two  of  the  valves  lie  the  orfices  of 
the  two  coronary  arteries;  of  which  the  left  is  the 
larger. 


CHAPTER    IX. 

DISSECTION    OF    THE    MUSCLES  OF 
THE  FACE. 

UNDER  the  integuments  of  the  face,  there  is  always 
a  considerable  quantity  of  adipose  membrane;  many  of 
the  muscles  are  very  slender,  and,  lying  embedded  in 
this  fat,  require  careful  dissection.  The  whole  side 
of  the  face  is  also  supplied  with  numerous  ramifications 
of  the  fascial  nerve,  or  portio  dura  of  the  seventh  pair. 
These  nervous  twigs  are  generally  removed  with  the 
integuments. 

Twelve  pair  of  muscles,  and  one  single  muscle,  are 
described  in  this  dissection. 


132  LONDON    DISSECTOR,  OR 

1 .  The  ORBICULARIS  PALPEBRARUM  or  orbicularis 
oculi — Arises,  from  the  internal  angular  process  of  the 
frontal  bone,  and  from  a  tendon  at  the  inner  angle  of 
the  eye,  by  a  number  of  fleshy  fibres  which  pass  round 
the  orbit,  covering  first  the  superior,  and  then  the 
inferior  eye-lid,  and  also  the  bony  edges  of  the  orbit. 

Inserted,  by  a  short  round  tendon,  into  the  nasal 
process  of  the  superior  maxillary  bone. 

This  muscle  is  intermixed,  at  its  upper  part,  with 
the  occipito-frontalis;  it  covers  the  upper  part  of  the 
lacrymal  sac,  and  should  be  divided  into  the  external 
and  internal  muscles.  The  internal  is  the  dliaris 
which  covers  the  cartilages  of  the  eye-lids,  which 
are  called  the  Cilia  or  Tarsi. 

Use:  To  shut  the  eye,  by  bringing  down  the  upper 
lid,  and  pulling  up  the  lower;  the  fibres  contracting 
towards  the  inner  angle,  as  to  a  fixed  point,  compress 
the  eye-ball  and  lacrymal  gland,  and  convey  the  tears 
towards  the  puncta  lacrymalia. 

.2.  The  CORRUGATOR  SUPERCILII — Arises,  fleshy, 
from  the  internal  angular  process  of  the  os  frontis;  it 
runs  outwards  and  a  little  upwards,  to  be 

Inserted  into  the  inferior  fleshy  part  of  the  occipito- 
frontalis  muscle,  extending  outwards  as  far  as  the  mid- 
dle of  the  superciliary  ridge. 

This  muscle  is  concealed  by  the  occipito-frontalis. 
It  lies  close  to  the  upper  and  inner  part  of  the  orbicu- 
laris palpebrarum,  with  which  it  is  connected. 

Use:  To  smooth  the  skin  of  the  forehead,  by  pulling 
it  down  after  the  action  of  the  occipito-frontalis. 
When  it  acts  more  forcibly,  it  pulls  down  the  eye- 
brow and  skin  of  the  forehead,  and  produces  vertical 
wrinkles. 

3.  The  COMPRESSOR  NARIS — Arises,  narrow,  from 
the  outer  part  of  the  ala  nasi,  and  neighbouring  part 
of  the  os  maxillare  superius.  From  this  origin  a 


GUIDE    TO    ANATOMY.  133 

number  of  thin  separate  fibres  run  up  obliquely  along  the 
cartilage  of  the  nose  toward  the  dorsum  nasi,  where 
the  muscle  joins  its  fellow,  and  is 

Inserted,  slightly,  into  the  lower  part  of  the  os  nasi 
and  nasal  process  of  the  superior  maxillary  bone. 

It  is  superficial;  its  origin  is  connected  with  the 
levator  labii  superioris  alaeque  nasi;  and  its  upper  part 
with  some  of  the  descending  fibres  of  the  occipito- 
frontalis. 

Use:  To  compress  the  ala  towards  the  septum  nasi; 
but,  if  the  fibres  of  the  occipito-frontalis,  which 
adhere  to  it,  act,  the  upper  part  of  this  muscle  assists 
in  drawing  the  ala  outwards.  It  also  corrugates  the 
skin  of  the  nose. 

4.  LEVATOR  LABII  SUPERIORIS  Ai^auE  NASI — 
Jlrises  by  two  distinct  origins;  the  first  from  the  nasal 
process  of  the  superior  maxillary  bone,  where  it  joins 
the   os   frontis   at  the  inner  canthus  of  the  eye;  it 
descends  along  the  nasal  process,  and  is  inserted  into 
the  outer  part  of  the  ala  nasi,  and  into  the  upper  lip. 
The  second  arises,  broad  and  fleshy,  from  the  external 
orbitar  process  of  the  superior  maxillary  bone,  imme- 
diately above  the  foramen  infra-orbitarium;  it  runs 
down,  becoming  narrower,  and  is  inserted  into  the 
upper  lip  and  orbicularis  oris. 

The  first  portion  of  this  muscle  is  sometimes  called 
Levator  Labii  Superioris  Alasque  Nasi;  and  the 
second,  Levator  Labii  Superioris  Proprius.  Their 
origins  are  partly  covered  by  the  orbicularis  palpe- 
brarum.  They  descend  more  outwardly  than  the  ala 
nasi. 

Use:  To  raise  the  upper  lip  and  dilate  the  nostril. 

The  infra-orbitary  artery,  vein,  and  nerve,  are  seen 
emerging  from  the  infra-orbitary  foramen  under  this 
muscle. 

5.  ZYGOMATICUS  MINOR — (often  wanting)  Jlrises 


134  LONDON    DISSECTOR,  OR 

from  the  upper  prominent  part  of  the  os  malee,  and, 
descending  obliquely  downwards  and  forwards,  is 

Inserted  into  the  upper  lip  near  the  corner  of  the 
mouth. 

Use:  To  draw  the  corner  of  the  mouth  and  upper 
lip  obliquely  upwards  and  outwards. 

6.  ZYGOMATICUS  MAJOR — Jlrises,  fleshy,  from  the 
os  malae,  near  the  zygomatic  suture. 

Inserted  into  the  angle  of  the  mouth,  appearing  to 
be  lost  in  the  depressor  anguli  oris,  and  orbicularis 
oris. 

Its  origin  is  partially  covered  by  the  orbicularis 
palpebrarum;  it  lies  more  outwardly  than  the  zygo- 
maticus  minor. 

Use:  To  draw  the  corner  of  the  mouth  and  under 
lip  upwards  and  outwards. 

7.  The  LEVATOR  ANGULI  ORIS,  or  Levator  labiorum 
communis — Arises,  thin  and  fleshy,  from  a  depression 
of  the  superior  maxillary  bone,  between  the  root  of 
the  socket  of  the  first  dens  molaris,  and  the  foramen 
infra-orbitarium. 

Inserted  into  the  angle  of  the  mouth. 

It  lies  more  outwardly  than  the  levator  labii  supe- 
rioris  alaeque  nasi,  and  is  in  part  concealed  by  that 
muscle,  by  the  zygomaticus  minor,  and  part  of  the 
zygomaticus  major.  At  its  insertion  it  is  particularly 
connected  with  the  depressor  anguli  oris. 

Use:  To  draw  the  corner  of  the  mouth  upwards. 

8.  The  DEPRESSOR  ANGULI  ORIS — Jlrises,  broad 
and  fleshy,  from  the  base  of  the  maxillary  bone,  near 
the  chin,  and,  gradually  becoming  narrower,  is 

Inserted,  into  the  angle  of  the  mouth,  uniting  with  the 
zygomaticus  major,  and  levator  anguli  oris:  it  is  also 
firmly  connected  with  the  platysma  myoides. 

Use:  To  pull  down  the  corner  of  the  mouth. 

9.  The  DEPRESSOR  LABII  INFERIORIS,  or  Quad- 
ratus  Genae — Jlrises,  fleshy  and  broad,  from  the  side 


GUIDE    TO    ANATOMY.  135 

of  the  lower  jaw,  a  little  above  its  lower  edge;  it  runs 
obliquely  upwards  and  inwards,  and  is 

Inserted  into  the  edge  of  the  under  lip. 

This  muscle,  at  its  insertion,  decussates  with  its 
fellow.  It  is  in  part  covered  by  the  depressor  anguli 
oris,  and  forms  the  thick  part  of  the  chin,  and  has  its 
fibres  interwoven  with  fat. 

Use:  To  pull  the  under  lip  downwards. 

10.  The  BUCCINATOR — Arises,  tendinous  and  fleshy, 
from  the  lower  jaw,  as  far  back  as  the  root  of  the 
coronoid  process;  from  the  upper  jaw,  as  far  back  as 
the  pterygoid  process  of  the  sphenoid  bone;  it  then  con- 
tinues to  arise  from  the  alveolar  processes  of  both  jaws, 
as  far  forwards  as  the  dentes  cuspidati.  The  fibres 
run  forwards,  and  are 

Inserted  into  the  angle  of  the  mouth. 

This  muscle  lies  deep,  adheres  to  the  membrane 
that  lines  the  mouth;  and  a  quantity  of  fat  is  always 
found  between  its  fibres  and  the  other  muscles  and 
integuments.  It  is  partly  concealed  by  the  masseter, 
and  by  the  muscles  which  pass  to  the  angle  of  the 
mouth,  as  the  levator  and  depressor  anguli  oris,  and 
zygomaticus  major.  It  is  inserted  behind  these  mus- 
cles. In  the  cheek  it  is  connected  with,  the  platysma 
myoides,  and  is  perforated  by  the  duct  of  the  parotid 
gland. 

Use:  To  draw  the  angle  of  the  mouth  backwards 
and  outwards,  and  to  contract  its  cavity,  by  pressing 
the  cheek  inwards. 

The  single  muscle  is  the 

ORBICULARIS  ORIS. — It  consists  of  two  planes  of 
semicircular  fibres,  which  decussate  at  the  angles  of 
the  mouth.  These  fibred  are  formed  chiefly  by  the 
muscles  which  are  inserted  into  the  lips;  they  sur- 
round the  mouth.  The  superior  portion  runs  along 
the  upper  lip,  the  inferior  along  the  lower. 

It  is  connected  and  intermixed  with  the  insertions 


136  LONDON    DISSECTOR,  OR 

of  all  the  preceding  muscles  of  the  face.  Some  of 
the  fibres  are  connected  to  the  septum  nasi,  and  are 
by  Albinus  termed  Nasalis  Labii  Superioris. 

Use:  To  shut  the  mouth,  by  contracting  and  draw- 
ing both  lips  together;  and  to  antagonize  the  muscles 
inserted  into  the  lips. 

11.  DEPRESSOR  LABII  SUPERIORIS  AL,£auE  NASI, 
•Arises,  thin  and  fleshy,  from  the  os  maxillare  supe- 
rius,  where  it  forms  the  alveoli  of  the  dentes  incisivi 
and  dens  canirrus;  thence  it  runs  up  under  part  of  the 
levator  labii  superioris  ataque  nasi. 

Inserted  into  the  upper  lip  and  root  of  the  ala  nasi. 

It  is  concealed  by  the  orbicularis  oris  and  levator 
labii  superioris  alaeque  nasi,  but  may  be  discovered 
by  inverting  the  upper  lip,  and  dissecting  on  the  side 
of  the  frenum  which  connects  the  lip  to  the  gums. 

Use:  To  draw  the  upper  lip  and  ala  nasi  down- 
wards and  backwards,  and  to  compress  the  nostril. 

12.  The  LEVATOR  LABII  INFERIORIS  or  Superbus. 
Arises  from  the  lower  jaw  at  the  root  of  the  alveolus 
of  the  lateral  incisor. 

Inserted  into  the  under  lip  and  skin  of  the  chin. 

These  two  small  muscles  are  found  by  the  side  of 
the  frenum  of  the  lower  lip.  They  lie  under  the 
depressor  labii  inferioris. 

Use:  To  raise  the  under  lip  and  skin  of  the  chin, 
and  to  protrude  the  lip. 

We  have  still  remaining  two  strong  muscles  on  the 
side  of  the  face,  and  two  other  muscles  concealed  by 
the  angle  of  the  inferior  maxilla. 

1.  The  MASSETER  is  divided  into  two  portions, 
which  decussate  one  another. 

The  anterior  portion  arises,  tendinous  and  fleshy, 
from  the  superior  maxillary  bone,  where  it  joins  the 
os  malae;  from  the  lower  edge  of  the  os  malae,  and 
from  its  zygomatic  process.  The  strong  fibres  run 
obliquely  downwards  and  backwards,  and  are  inserted 
into  the  outside  of  the  angle  of  the  lower  jaw, 


GUIDE    TO    ANATOMY.  137 

The  Posterior  portion  arises,  principally  fleshy, 
from  the  inferior  surface  of  the  os  malae,  and  of  the 
whole  of  the  zygomatic  process,  as  far  back  as  the 
tubercle  before  the  socket  for  the  condyle  of  the 
lower  jaw.  The  fibres  run  forward,  and  are  inserted, 
tendinous,  into  the  outer  surface  of  the  coronoid  process 
of  the  lower  jaw. 

The  anterior  portion  conceals  almost  the  whole  of 
the  posterior.  The  greater  part  of  this  muscle  is 
superficial. 

Use:  To  pull  up  the  lower  jaw,  for  performing  the 
grinding  or  lateral  motions. 

2.  TEMPORALIS — Arises,  fleshy,  from  a  semicircu- 
lar ridge  in  the  lower  and  lateral  part  of  the  parietal 
bone,  from  all  the  squamous  portion  of  the  temporal 
bone,  from  the  external  angular  process  of  the  os 
frontis,  from  the  temporal  process  of  the  sphenoid 
bone,  and  from  an  aponeurosis  which  covers  the  mus- 
cle. From  these  different  origins  the  fibres  converge, 
descend  under  the  bony  jugum  formed  by  the  zygo- 
matic processes  of  the  temporal  and  cheek  bones. 

Inserted,  by  a  strong  tendon,  into  the  upper  part  of 
the  coronoid  process  of  the  lower  jaw,  to  which  it 
adheres  on  every  side,  but  more  particularly  on  its 
anterior  part. 

Its  insertion  is  concealed  by  the  jugum  and  by  the 
masseter;  so  that,  to  expose  it,  the  masseter  must  be 
cut  away. 

Use:  To  raise  the  lower  jaw. 

To  expose  the  following  muscles,  we  must  remove 
those  of  the  cheek  and  jaw;  the  masseter  and  the 
insertion  of  the  temporalis  must  be  taken  away,  and 
the  coronoid  process  of  the  inferior  maxilla  removed 
by  a  saw. 

3.  The  PTERYGOIDEUS  EXTERNUS— Arises,  from 
the  outer  side  of  the  external  plate  of  the  pterygoid 
process  of  the  sphenoid  bone,  from  part  of  the  tube- 

12* 


138  LONDON    DISSECTOR,  OB 

rosity  of  the  os  maxillare  adjoining  to  it,  and  from  the 
root  of  the  temporal  process  of  the  sphenoid  bone. 
It  passes  backwards  and  outwards,  to  be 

Inserted  into  a  depression  in  the  neck  of  the  condy- 
loid  process  of  the  lower  jaw,  and  into  the  anterior 
and  inner  part  of  the  ligament  of  the  articulation  of 
that  bone. 

This  muscle  passes  almost  transversely  from  the 
skull  to  its  insertion.  It  is  concealed  by  the  muscles 
of  the  face  and  neck,  and  by  the  ascending  processes 
of  the  lower  jaw. 

Use:  When  this  pair  of  muscles  act  together,  they 
bring  the  jaw  horizontally  forwards.  When  they  act 
singly,  the  jaw  is  moved  forwards,  and  to  the  oppo- 
site side. 

4.  The  PTERYGOIDEUS  INTERNUS — Arises,  tendi- 
nous and  fleshy,  from  the  inner  and  upper  part  of  the 
internal  plate  of  the  pterygoid  process  of  the  sphenoid 
bone,  filling  all  the  space  between  the  two  plates;  and 
from  the  pterygoid  process  of  the  os  palati  between 
these  plates. 

Inserted,  by  tendinous  and  fleshy  fibres,  into  the 
inside  of  the  angle  of  the  lower  jaw. 

To  expose  this  muscle,  the  jaw  must  be  removed 
from  its  articulating  cavity,  and  then  pulled  forwards, 
and  toward  the  opposite  side;  or  it  may  be  sawn 
across  at  its  sympyhsis,  and  the  other  half  removed. 
It  is  larger  than  the  pterygoideus  externus;  and 
betwixt  the  two  muscles  there  is  a  considerable  quan- 
tity of  cellular  membrane,  and  the  trunk  of  the  inferior 
maxillary  and  gustatory  nerves.  Like  that  muscle,  it 
is  concealed  by  the  lower  jaw  and  facial  muscles. 
Along  its  posterior  edge  we  observe  the  Ligamentum 
Laterale  Maxillae  Inferioris,  a  ligamentous  band,  which 
extends  from  the  back  part  of  the  styloid  process  to 
the  angle  of  the  lower  jaw. 


GUIDE    TO    ANATOMY.  139 

Use:  To  draw  the  jaw  upwards,  and  obliquely 
towards  the  opposite  side,  or  to  move  it  laterally. 

On  the  side  of  the  face  is  situated  a  considerable 
salivary  gland,  the  PAROTID  GLAND,  a  large  white 
mass,  irregularly  oblong  and  protuberant,  filling  up  all 
the  space  between  the  angle  and  the  ascending  pro- 
cesses of  the  jaw,  the  mastoid  process,  root  of  the 
cartilage  of  the  ear,  and  zygomatic  process  of  the 
temporal  bone.  From  its  anterior  and  upper  part  a 
white  canal  or  duct  passes  forwards  over  the  masse- 
ter,  and  perforates  the  buccinator  from  without 
inwards,  opening  into  the  mouth  opposite  the  first 
dens  molaris.  The  coats  of  this  duct  are  very  thick 
and  firm,  consisting  of  a  ligamentous  substance. 


CHAPTER  X. 

DISSECTION    OF    THE    THROAT. 

ON  looking  into  the  mouth,  we  observe  a  soft  cur- 
tain hanging  from  the  palate  bones,  named  the  VELUM 
PENDULUM  PAL  ATI,  or  soft  Palate.  The  apex  of  the 
velum  forms  a  small  projecting  glandular  body,  termed 
the  UVULA,  or  pap  of  the  throat.  From  each  side  of 
the  Uvula,  two  muscular  half  arches  or  columns  are 
sent  down,  the  anterior  to  the  root  of  the  tongue,  the 
posterior  to  the  side  of  the  pharynx.  Between  these 
half  arches  on  each  side,  are  situated  the  glands  termed 
Amygdala,  or  tonsils.  The  common  opening  behind 
the  anterior  arch  is  named  the  Fauces,  or  Top  of  the 
Throat,  from  which  there  are  six  passages,  two  up- 
wards, being  one  to  each  nostril,  called  the  Posterior 
Nostrils;  two  at  the  sides,  called  Eustachian  Tubes, 


140  LONDON    DISSECTOR,  Oil 

passing  on  each  side  to  the  ear;*  two  downwards,  of 
which  the  anterior  is  the  passage  through  the  glottis 
and  larynx  into  the  trachea;  the  posterior,  which  is  the 
largest,  is  the  pharynx,  or  top  of  the  oesophagus,  and 
leads  to  the  stomach. 

MUSCLES    SITUATED    ABOUT   THE    ENTRY    OF   THE 
FAUCES. 

These  consist  of  four  pairs,  and  a  single  muscle  in 
the  middle. 

1.  CONSTRICTOR  ISTHMI  FAUCIUM — Arises,  by  a 
slender  beginning,  from  the  side  of  the  tongue,  near 
its  root;  thence  running  upwards  within  the  anterior 
arch,  before  the  amygdala,  it  is 

Inserted  into  the  middle  of  the  velum  pendulum  pal- 
ati,  as  far  as  the  root  of  the  uvula.  It  is  here  connected 
with  its  fellow,  and  with  the  beginning  of  the  palato- 
pharyngeus. 

Situation:  It  forms  the  anterior  half  arch. 

Use:  To  draw  the  velum  towards  the  root  of  the 
tongue,  which  at  the  same  time  it  raises;  and,  with  its 
fellow,  to  contract  the  opening  into  the  fauces. 

2.  The  PALATO-PHARYNGEUS — Arises,  by  a  broad 
beginning,  from  the  root  of  the  uvula  in  the  middle  of 
the  velum  pendulum  palati,  and  from  the  tendinous  ex- 
pansion of  the  circumflexus  palati.      The  fibres  pass 
along  the  posterior  arch  behind  the  amygdalae,  and  run 
backwards  to  the  superior  and  lateral  part  of  the  pha- 
rynx, where  they  are  scattered,  and  mixed  with  those 
of  the  stylo-pharyngeus. 

Inserted  into  the  edge  of  the  upper  and  back  part  of 

*  A  probe  may  be  introduced  through  the  anterior  nostrils  into  the 
Eustachian  tube;  the  tube  opens  into  the  pharynx  in  a  direction  opposite 
to  the  space  between  the  roots  of  the  middle  and  inferior  turbinated 

bones. 


GUIDE   TO   ANATOMY.  141 

the  thyroid  cartilage,  and  into  the  back  part  of  the 
pharynx;  thus  forming  the  posterior  half  arch  or 
column. 

Use:  To  draw  the  uvula  and  velum  downwards  and 
backwards,  and  pull  the  thyroid  cartilage  and  pharynx 
upwards;  to  shut  the  passage  into  the  nostrils,  and,  in 
swallowing,  to  thrust  the  food  from  the  fauces  into  the 
pharynx. 

The  S  ALPINGO-PHARYNGEUS  of  Albinus  is  composed 
of  a  few  fibres  of  this  muscle,  which  arise  from  the  an- 
terior and  lower  part  of  the  cartilaginous  extremity  of 
the  Eustachian  tube,  and  are  inserted  into  the  inner  part 
of  the  last  mentioned  muscle. 

3.  The  CIRCUMFLEXUS,  or  Tensor  Palati, — Arises^ 
from  the  spinous  process  of  the  sphenoid  bone,  behind 
the  foramen  ovale,  and  from  the  Eustachian  tube  near 
its  osseous  part;  it  runs  down  along  the  pterygoideus 
internus,  and  forms  a  round  tendon,  which  passes  over 
the  hook  of  the  internal  plate  of  the  pterygoid  process 
of  the  sphenoid  bone,  and  soon  spreads  into  a  broad 
tendinous  expansion. 

Inserted  into  the  velum  pendulum  palati,  and  semi- 
lunar  edge  of  the  os  palati. 

Its  insertion  extends  as  far  as  the  suture  which  joins 
the  two  ossa  palati.  Some  of  its  posterior  fibres 
generally  join  with  the  constrictor  pharyngis  superior 
and  palato-pharyngeus. 

Use:  To  stretch  the  velum,  and  draw  it  downwards, 
and  to  one  side. 

4.  The  LEVATOR  PALATI — Mses,  tendinous  and 
fleshy,  from  the  extremity  of  the  petrous  portion  of 
the  temporal  bone,  and  from  the  Eustachian  tube. 

Inserted  into  the  whole  length  of  the  velum  pendu- 
lum palati,  as  far  as  the  root  of  the  uvula,  uniting  with 
its  fellow. 

Use:  To  draw  the  velum  upwards  and  backwards, 


142  LONDON    DISSECTOR,  OR 

so  as  to  shut  the  passage  from  the  fauces  into  the 
mouth  and  nose. 

The  single  muscle  is  the 

AZYGOS  UVUL^:. — It  arises,  fleshy,  from  the  extrem- 
ity of  the  suture  which  unites  the  ossa  palati;  runs 
down  the  whole  length  of  the  velum,  like  a  small 
earth-worm,  adhering  to  the  tendons  of  the  circum- 
flexi  palati. 

Inserted  into  the  tip  of  the  uvula. 

Use:  To  raise  the  uvula  upwards  and  forwards,  and 
shorten  it. 

MUSCLES    ON    THE    BACK   PART   OF    THE    PHARYNX. 

Of  these  there  are  three  pair. 

1.  The  CONSTRICTOR  PHARYNGIS  INFERIOR.  This 
muscle  arises,  from  the  outside  of  the  ala  of  the 
thyroid  cartilage,  near  the  attachment  of  the  thyro- 
hyoideus  muscle,  and  from  the  side  of  the  cricoid 
cartilage,  near  the  crico-thyroideus. 

Inserted  into  the  white  line  on  the  back  part  of  the 
pharynx,  where  it  is  united  to  its  fellow. 

This  muscle  covers  the  under  part  of  the  middle 
constrictor;  the  superior  fibres  run  obliquely  upwards, 
while  the  inferior  fibres  have  a  transverse  direction, 
and  surround  the  oesophagus. 

Use:  To  compress  that  part  of  the  pharynx  which 
it  covers,  and  to  raise  it  with  the  larynx  a  little 
upwards. 

2.  The  CONSTRICTOR  PHARYNGIS  MEDIUS — Arises 
from  the  superior  edge  of  the  cornu  of  the  os  hyoides, 
extending  as  far  forwards  as  the  graniform  process,  or 
appendix;  and  from  the  ligament  which  connects  the 
os  hyoides  to  the  thyroid  cartilage.     The  superior 
fibres  ascend  obliquely,  the  others  run  more  trans- 
versely. 

Inserted  into  the  cuneiform  process  of  the  os  occip- 
itis,  before  the  foramen  magnum,  and  into  a  white 


GUIDE    TO    ANATOMY.  143 

line  in  the  middle  of  the  posterior  surface  of  the 
pharynx,  where  it  is  joined  to  its  fellow. 

The  lower  part  of  this  muscle  is  covered  by  the 
muscle  last  described,  while  the  upper  part  covers  the 
inferior  fibres  of  the  constrictor  superior. 

Use:  To  compress  that  part  of  the  pharynx  which 
it  invests,  and  to  draw  it  and  the  os  hyoides  upwards. 

3.  CONSTRICTOR  PHARYNGIS  SUPERIOR — Arises, 
above,  from  the  cuneiform  process  of  the  os  occipitis, 
before  the  foramen  magnum;  lower  down  from  the 
pterygoid  process  of  the  sphenoid  bone;  from  the 
upper  and  under  jaw,  near  the  alveolar  processes  of 
the  last  dentes  molares;  and  from  the  back  part  of  the 
buccinator  muscle.  Some  fibres  also  come  from  the 
root  of  the  tongue,  and  from  the  palate. 

Inserted  into  a  white  line  in  the  middle  of  the  pos- 
terior surface  of  the  pharynx. 

The  larger  part  of  this  muscle  is  covered  by  the 
constrictor  medius. 

Use:  To  compress  the  upper  part  of  the  pharynx, 
and  draw  it  forwards  and  upwards. 

A 

MUSCLES   OF   THE    LARYNX. 

The  Larynx  is  composed  of  five  Cartilages:  1 .  The 
THYROID  CARTILAGE,  situated  immediately  below  the 
os  hyoides  in  the  middle  of  the  throat.  2.  The  CRI- 
COID  Cartilage,  situated  immediately  below  the  thy- 
roid cartilage,  betwixt  it  and  the  superior  rings  of 
the  trachea.  3.  The  EPIGLOTTIS,  a  broad  triangular 
cartilage,  very  elastic,  situated  behind  the  root  of  the 
tongue,  and  covering  the  entrance  into  the  upper  part 
of  the  larynx.  4  &  5.  The  arytaenoid  cartilages,  two 
small  bodies,  like  peas,  situated  behind  the  thyroid 
cartilage,  on  the  upper  edge  of  the  back  part  of  the 
cricoid  cartilage,  and  between  the  two  alae  or  wings 
of  the  thyroid  cartilage.  These  two  small  cartilages 


144  LONDON    DISSECTOR,  OR 

form  between  themselves  and  the  thyroid  a  longitu- 
dinal fissure,  extending  from  before  backwards,  which 
is  called  the  Glottis,  or  Rima  Glottidis,  and  leads  to 
the  trachea. 

The  muscles  situated  about  the  glottis  consist  of 
four  pairs  of  small  muscles,  and  a  single  one. 

1.  The  CRICO-ARYTJENOIDEUS  'PosTicus — Arises, 
fleshy,  from  the  posterior  part  of  the  cricoid  cartilage. 

Inserted,  narrow,  into  the  back  part  of  the  arytae- 
noid  cartilage  of  the  same  side. 

Use:  To  open  the  rima  glottidis  a  little,  and,  by 
pulling  back  the  arytaenoid  cartilage,  to  render  the 
ligament  of  the  glottis  tense. 

2.  The  CRICO-ARYT^NOIDEUS  LATERALIS — Arises, 
fleshy,  from  the  side  of  the  cricoid  cartilage,  where 
it  is  covered  by  the  ala  of  the  thyroid  cartilage. 

Inserted  into  the  outer  side  of  the  arytaenoid  carti- 
lage, lying  more  forward  than  the  last  described 
muscle. 

Use:  To  open  the  rima  glottidis,  by  pulling  the 
ligaments  from  each  other. 

3.  The  THYRO-ARYTJSNOIDEUS — Arises  from  the 
middle  and  inferior  part  of  the  posterior  surface  of 
the  thyroid  cartilage;  runs  backwards,  and  a  little 
upwards,  and  is 

Inserted  into  the  fore  part  of  the  arytaenoid  carti- 
lage, farther  forward  than  the  muscle  last  described. 

Use:  To  pull  the  arytaenoid  cartilage  forwards,  and 
thus  shorten  the  ligament  of  the  larynx  or  glottis. 

4.  ARYT^NOIDEUS  OBLIQ.UUS — Arises  from  the  base 
of  one  arytaenoid  cartilage;  and,  crossing  its  fellow,  is 

Inserted  into  the  tip  of  the  other  arytaenoid  carti- 
lage. 

•  Use:  When  both  act,  they  pull  the  arytaenoid  carti- 
lages towards  each  other. 

The  single  muscle  is  the 

ARYT^ENOIDEUS  TRANSVERSUS,  which  arises  from 


GUIDE    TO    ANATOMY.  145 

the  whole  length  of  one  arytasnoid  cartilage,  and  passes 
across  to  be 

Inserted  into  the  whole  length  of  the  other  arytaenoid 
cartilage. 

It  is  situated  anterior  to  the  arytaenoidei  obliqui. 

Use:  To  shut  the  rima  glottidis,  by  bringing  the 
arytasnoid  cartilages  together: 

On  each  side  of  the  larynx,  there  are  also  a  few  mus- 
cular fibres,  which  are  named  as  follows. 

1 .  THYRO-EPIGLOTTIDEUS — Jlrising,  by  a  few  pale 
separated  fibres  from  the  thyroid  cartilage,  and 

Inserted  into  the  side  of  the  epiglottis. 

Use:  To  draw  the  epiglottis  obliquely  downwards, 
or,  when  both  muscles  act,  directly  downwards;  and 
at  the  same  time  to  expand  it. 

2.  The  ARYTJENO-EPIGLOTTIDEUS — Arises,  by  a 
few  slender  fibres,  from  the  lateral  and  upper  part  of 
the  arytaenoid  cartilage,  and  is 

Inserted  into  the  epiglottis,  along  with  the  former 
muscle. 

Use:  When  both  muscles  act,  to  pull  the  epiglottis, 
close  upon  the  glottis. 


13 


CHAPTER    XI. 

DISSECTION    OF    THE    ORBIT   OF 
THE    EYE. 


THE  globe  or  ball  of  the  eye  is  situated  about  the 
middle  of  the  orbit.  It  is  connected  to  the  bone  by  its 
muscles,  and  by  the  optic  nerve;  and  all  these  parts  are 
embedded  posteriorly  in  a  soft,  fatty  substance,  which 
fills  up  the  bottom  of  the  orbit.  The  tunica,  or  mem- 
brana  conjunctiva,  is  seen  lining  the  inner  surface  of 
the  eye-lids,  and  reflected  from  them  over  the  anterior 
part  of  the  globe  of  the  eye,  so  that  the  back  part  of  the 
eye-ball,  and  all  the  muscles  and  nerves,  are  situated 
behind  it.  This  membrane  must  therefore  be  dissected 
away;  the  upper  part  of  the  orbit,  which  is  formed  by 
the  os  frontis,  must  be  removed  with  a  saw,  and  the 
fat  surrounding  the  muscles,  vessels,  and  nerves,  cau- 
tiously dissected  away  with  the  scissors. 

MUSCLES    SITUATED    WITHIN    THE    ORBIT. 

Seven  muscles  are  contained  within  the  orbit,  of 
which  one  belongs  to  the  upper  eye-lid,  and  six  to  the 
globe  of  the  eye. 

1.  The  LEVATOR  PALPEBR.SE  SUPERIORIS — Arises, 
by  a  small  tendon,  from  the  upper  part  of  the  foramen 
opticum  of  the  sphenoid  bone;  the  tendon  forms  a  broad 
flat  belly. 

Inserted,  by  a  broad  thin  tendon,  into  the  upper  eye- 
lid, adhering  to  the  tarsal  cartilage,  which  gives  form 
to  the  eye-lid. 


GUIDE    TO    ANATOMY.  147 

Use:  To  open  the  eye,  by  drawing  the  superior 
eye-lid  upwards. 

There  are  four  straight  muscles,  orrecti,  belonging 
to  the  globe  of  the  eye.  These  four  muscles  resemble 
each  other,  all  arising  by  narrow  tendons  from  the  mar- 
gin of  the  foramen  opticum,  where  they  surround  the 
optic  nerve;  all  forming  strong  fleshy  bellies,  and  in- 
serted, by  broad,  thin  tendons,  at  the  fore  part  of  the 
globe  of  the  eye,  into  the  tunica  sclerotica,  or  outer 
tunic  of  the  eye,  and  under  the  tunica  conjunctiva. 
They  are  distinguished  from  each  other  by  the  terms 
Levator,  Depressor,  Abductor  and  Adductor. 

2.  The  LEVATOR  OCULI — Arises,  by  a  narrow  ten- 
don, from  the  upper  part  of  the  foramen  opticum  of  the 
sphenoid  bone;  it  forms  a  fleshy  belly,  and  is 

Inserted  into  the  superior  and  anterior  part  of  the 
tunica  sclerotica,  by  a  broad  thin  tendon. 

It  lies  below  the  levator  palpebrae  superioris,  and 
raises  the  globe  of  the  eye. 

3.  The  DEPRESSOR  OCULI — Arises  horn  the  inferior 
margin  of  the  foramen  opticum,  and  is 

Inserted  into  the  inferior  and  anterior  part  of  the  tu- 
nica sclerotica. 

Use:  To  move  the  globe  of  the  eye  downwards. 

4.  The  ADDUCTOR  OCULI— Arises  from  the  inner 
part  of  the  foramen  opticum,  and  is     • 

Inserted  into  the  inner  and  anterior  part  of  the  tunica 
sclerotica. 

It  is  the  shortest  of  the  four  recti  muscles,  and  draws 
the  eye  towards  the  nose. 

5.  The  ABDUCTOR  OCULI — Arises  from  the  outer 
part  of  the  foramen  opticum. 

Inserted  into  the  outer  part  of  the  tunica  sclerotica. 
It  is  the  longest  of  the  recti,  and  moves  the  globe 
outwards. 

The  next  two  are  the  oblique  muscles. 


148 

6.  The  OBLKIUUS  SUPERIOR,  or  Trochlearis,  Arises, 
by  a  small  tendon,  from  the  margin  of  the  foramen  op- 
ticum,  between  the  levator  and  abductor  oculi.     Its 
long  slender  belly  runs  along  the  inner  side  of  the  orbit 
to  the  internal  angular  process  of  the  os  frontis,  where 
a  cartilaginous  pulley  is  fixed.    The  muscle  then  forms 
a  tendon,  which  •  passes  through  the  pulley,  runs  ob- 
liquely down  wards  and  outwards,  inclosed  in  a  mem- 
branous sheath;  and  becoming  broader  and  thinner,  is 

Inserted  into  the  tunica  sclerotica,  about  half  way 
between  the  insertion  of  the  levator  oculi,  and  the 
entrance  of  the  optic  nerve. 

Use:  To  roll  the  globe  of  the  eye,  and  turn  the 
pupil  downwards  and  outwards. 

7.  The  OfiLiauus  INFERIOR — Arises,  narrow,  and 
principally   tendinous,  from  the   outer  edge  of  the 
orbitar  process  of  the  superior  maxillary  bone,  near 
its  junction  with  the  os  unguis.     It  runs  obliquely  out- 
wards and  backwards,  under  the  depressor  oculi,  and  is 

Inserted,  by  a  broad  thin  tendon,  into  the  sclerotica, 
between  the  entrance  of  the  optic  nerve,  and  the 
insertion  of  the  abductor  oculi. 

Use:  To  draw  the  globe  of  the  eye  forwards, 
inwards,  and  downwards,  and  to  turn  the  pupil  upwards. 

In  the  orbit,  we  also  meet  with  the  LACHRYMAL 
GLAND. — This  gland  is  of  a  yellowish  color,  it  is  situ- 
ated in  a  depression  of  the  os  frontis  near  the  temple. 
It  adheres  closely  to  the  fat  which  surrounds  the  mus- 
cles and  posterior  convexity  of  the  eye.  It  sends  off 
several  small  ducts  which  pierce  the  tunica  conjunctiva 
lining  the  upper  eye  lid;  these  ducts  cannot  be  seen, 
unless  the  part  be  macerated  in  water,  when  they  are 
filled  with  the  liquid. 

The  PUNCTA  LACHRYMALIA  are  two  small  holes 
near  the  internal  angle  of  the  palpebrae,  situated  one 
in  each  eye-lid.  They  lead  into  the  LACHRYMAL  SAC. 


GUIDE    TO    ANATOMY.  149 

This  sac  is  an  oblong  membranous  bag,  situated  at  the 
inner  angle  of  the  eye,  in  a  depression  formed  by  the 
os  unguis,  and  nasal  process  of  the  superior  maxillary 
bone.  It  receives  the  tears  by  the  puncta  lachrymalia, 
and  from  the  sac  they  are  conveyed  into  the  nose  by  a 
DUCT,  named  the  LACHRYMAL,  or  NASAL.  The  lower 
extremity  of  this  duct  opens  into  the  nose  on  one  side 
of  the  antrum  maxillare,  and  under  the  os  spongiosum 
inferius.  A  probe,  with  its  extremity  bent,  may  be 
introduced  from  the  nose  through  this  duct  into  the 
lachrymal  sac. 

The  Caruncula  Lachrymalis  is  a  small  reddish 
granulated  body,  situated  at  the  internal  angle  of  the 
palpebrae. 


CHAPTER    XII. 

DISSECTION  OF  THE  MUSCLES  ON 

THE   POSTERIOR   PART   OF  THE 

TRUNK  AND  NECK. 

FROM  the  number  and  intimate  connection  of  these 
muscles,  their  description  is  necessarily  complicated, 
and  their  dissection  difficult.  The  smaller  muscles, 
indeed,  cannot  be  separated  without  dividing  some  of 
their  fibres.  We  do  not  here,  as  in  the  limbs,  find  the 
muscles  distinctly  marked,  loosely  connected  by 
cellular  membrane,  and  separated  with  facility;  but 
closely  united,  and  in  many  places  having  their  fibres 
so  intermixed,  as  to  render  their  divisions  indis- 
tinct and  uncertain. 

In  this  dissection  we  meet  with  twenty-two  distinct 
pairs  of  muscles,  besides  a  number  of  small  muscles 
situated  between  the  processes  of  contiguous  vertebrae. 
13* 


150  LONDON    DISSECTOR,  OR 

On  removing  the  integuments  of  the  posterior  part 
of  the  neck  and  back,  which  may  be  done  by  making 
an  incision  along  the  whole  length  of  the  spine,  another 
from  the  tubercle  of  the  occipital  bone  to  the  acromion, 
and  a  third  from  the  acromion  to  the  last  dorsal  ver- 
tebra; we  expose, 

1.  The  TRAPEZIUS,  or  CUCULLARIS. — It  arises,  by 
a  thick  round  tendon,  from  the  lower  part  of  the  pro- 
tuberance in  the  middle  of  the  os  occipitis  behind,  and, 
by  a  thin  tendinous  expansion,  from  the  superior  trans- 
verse ridge  of  that  bone;  from  the  five  superior  cervi- 
cal spinous  processes  by  the  ligamentum  nuchse;  tendi- 
nous, from  the  two  inferior  cervical  spinous  processes, 
and  from  f,he  spinous  processes  of  all  the  vertebrae 
of  the  back.  The  fleshy  fibres  coming  from  the  neck 
descend  obliquely,  while  those  from  the  back  ascend. 

Inserted,  fleshy,  into  the  posterior  third  part  of  the 
clavicle;  tendinous  and  fleshy,  into  the  acromion,  and 
into  the  upper  edge  of  all  the  spine  of  the  scapula.  The 
fibres  slide  over  a  triangular  surface  at  the  extremity 
of  the  spine  of  that  bone. 

Situation:  This  muscle  is  quite  superficial,  and  con- 
ceals all  the  muscles  situated  in  the  posterior  part  of 
the  neck,  and  upper  part  of  the  back.  It  adheres  to 
its  fellow  the  whole  length  of  its  origin.  Its  anterior 
fibres  lie  posterior  to  those  of  the  sterno-mastoideus, 
but  are  not  in  contact  with  them,  a  considerable  quan- 
tity of  adipose  substance  being  interposed.  The  pos- 
terior cervical  ligament  (ligamentum  nuchae  vel  colli) 
is  a  ligament  which  arises  from  the  middle  of  the 
occipital  bone,  runs  down  on  the  back  part  of  the  neck, 
adhering  to  the  spinous  processes  of  the  cervical  ver- 
tebras, and  giving  origin  to  the  fibres  of  the  trapezius, 
and  of  other  muscles. 

Use:  To  move  the  scapula  in  different  directions. 
The  superior  fibres  draw  it  obliquely  upwards,  the 
middle  transverse  ones  draw  it  directly  backwards, 


GUIDE    TO    ANATOMY.  151 

and  the  inferior  fibres  move  it  obliquely  donwnwards 
and  backwards.  Also,  to  draw  back  the  head,  and 
contribute  to  its  rotatory  motions. 

This  muscle  should  now  be  reflected  from  the  spine 
and  head. 

2.  The  LATISSIMUS  DORSI— Arises.,  by  a  broad  thin 
tendon,  from  all  the  spinous  processes  of  the  os  sacrum, 
and  of  the  lumbar  vertebrae;  from  the  spinous  processes 
of  the  seven  inferior  dorsal  vertebrae;  from  the  poste- 
rior part  of  the  spine  of  the  os  ilium;  also  from  the  ex- 
tremities of  the  four  inferior  false  ribs,  by  four  distinct 
fleshy  dictations,  which  intermix  with  those  of  the 
obliquus  externus  abdominis.  The  inferior  fleshy 
fibres  ascend  obliquely;  the  superior  run  transversely: 
they  pass  over  the  inferior  angle  of  the  scapula  (from 
which  the  muscle  often  receives  a  thin  fasciculus  of 
fibres,)  to  reach  the  axilla,  where  they  are  all  collected 
and  twisted. 

Inserted,  by  a  strong  flat  tendon,  into  the  inner  edge 
of  the  groove  in  the  os  humeri,  which  receives  the  long 
tendon  of  the  biceps  flexor  cubiti. 

Where  this  muscle  arises  from  the  dorsal  vertebrae, 
it  is  concealed  by  the  origin  of  the  trapezius.  The 
remainder  of  it  is  placed  immediately  under  the  skin, 
and  covers  the  deeper  seated  muscles  of  the  loins  and 
back.  It  is  situated  superior  to  the  gluteus  maximus, 
and  posterior  to  the  obliquus  externus  abdominis.  -Its 
insertion  cannot  be  traced  till  the  muscles  of  the  arm 
are  dissected;  it  forms  the  fold  on  the  posterior  part  of 
the  hollow  of  the  arm  pit.  The  tendon  of  this  muscle, 
with  the  subjacent  tendon  of  the  serratus  posticus 
inferior,  assists  in  forming  the  fascia  lumborum. 

Use:  To  pull  the  arm  backwards  and  downwards, 
and  to  roll  the  os  humeri. 

Having  removed  the  trapezius  and  latissimus  dorsi, 
two  muscles  will  be  seen  passing  from  the  neck  to  the 
scapula. 


152  LONDON    DISSECTOR,  OR 

3.  The  RHOMBOIDEUS.  This  muscle  is  divided  into 
two  portions,  rhomboideus  major  and  minor. 

Rhomboideus  major  (the  inferior  portion)  arises,  ten- 
dinous, from  the  spinous  processes  of  the  four  or  five 
superior  dorsal  vertebrae. 

Inserted  into  all  the  base  of  the  scapula  below  its 
spine. 

Rhomboideus  minor  (the  superior  portion)  arises, 
tendinous  from  the  spinous  processes  of  the  three  in- 
ferior vertebrae  of  the  neck,  and  from  the  ligamentum 
nuches. 

Inserted  into  the  base  of  the  scapula,  opposite  to  the 
triangular  plain  surface  at  the  root  of  the  spine. 

Situation:  This  muscle  lies  beneath  the  trapezius 
and  latissimus  dorsi;  a  small  part  of  the  rhomboideus 
major  may  be  seen  between  these  muscles,  and  the 
inferior  part  of  the  base  of  the  scapula. 

Use:  To  draw  the  scapula  obliquely  upwards,  and 
directly  backwards. 

The  rhomboidei  should  now  be  reflected  from  the 
spine. 

4.  The  LEVATOR  SCAPULA — Jlrises  from  the  trans- 
verse processes  of  the  five  superior  vertebrae  of  the 
neck,  by  five  distinct,  tendinous,  and  fleshy  slips,  which 
unite  and  form  a  considerable  muscle. 

Inserted,  tendinous  and  fleshy,  into  the  base  of  the 
scapula,  above  the  root  of  the  spine,  and  under  the 
superior  angle  (not  into  the  angle  itself,  as  it  is  usually 
described.) 

This  muscle  is  concealed  by  the  trapezius  and  ster- 
no-mastoideus;  but  a  small  part  of  its  belly  may  be 
seen  in  the  space  between  the  edges  of  these  muscles. 
The  origin  of  the  levator  scapulae  is  partly  cocealed 
by  the  splenius  capitis;  and  the  digitations,  where  they 
arise  from  the  transverse  processes,  lie  betwixt  similar 
attachments  of  the  scaleni  muscles  before,  and  of  the 
splenius  colli  behind. 


GUIDE    TO    ANATOMY.  153 

Use:  To  draw  the  scapula  upwards,  and  a  little 
forwards. 

Detaching  the  rhomboideus  from  its  origin  in  the 
spine,  you  will  see  another  muscle  passing  from  the 
whole  of  the  basis  of  the  scapula. 

5.  The  SERRATUS  MAGNUS,  or  Serratus  Major  An- 
ticus — Jlrises  by  nine  fleshy  digitations,  from  the  nine 
superior  ribs.      These  digitations   are   seen  on  the 
anterior  part   of  the   thorax;    they  pass    obliquely 
backwards,  and  form  a  strong  fleshy  muscle. 

Inserted,  principally  fleshy,  into  the  whole  of  the 
base  of  the  scapula. 

This  muscle  lies  between  the  scapula  and  the  ribs, 
so  that,  to  see  its  course,  the  articulation  of  the  clavi- 
cle to  the  sternum  should  be  divided,  and  the  scapula 
lifted  from  the  trunk.  It  is  concealed  by  the  latissimus 
dorsi,  by  the  two  pectoral  muscles,  and  the  scapula. 
The  only  part  of  it  which  can  be  seen  before  the 
removal  of  those  muscles,  projects  betwixt  and  below 
them  on  the  side  of  the  trunk.  The  lower  digitations, 
which  pass  more  anteriorly  than  the  edge  of  the  latis- 
simus  dorsi,  are  intermixed  with  the  superior  digita- 
tions of  the  obliquus  externus  abdominis.  The  superior 
digitations  arise  behind  the  pectoralis  minor.  The 
insertion  of  the  muscle  is  between  the  subscapularis, 
which  arises  from  the  internal  surface  of  the  scapula, 
and  the  insertions  of  the  rhomboideus  and  levator 
scapula3. 

Use:  To  move  the  scapula  forwards,  and,  when  the 
scapula  is  forcibly  raised,  to  draw  the  ribs  upwards. 
The  upper  extremity  may  now  be  removed  from  the 
trunk. 

The  removal  of  the  rhomboideus  also  exposes, 

6.  The  SERRATUS  SUPERIOR  POSTICUS.    This  mus- 
cle arises,  by  a  thin  broad  tendon,  from  the  spinous 
processes  of  the  three  inferior  cervical  vertebra,  and 
of  the  two  superior  dorsal. 


154  LONDON    DISSECTOR,  OR 

Inserted,  by  distinct  fleshy  slips,  into  the  second, 
third,  fourth,  and  sometimes  the  fifth  ribs,  a  little 
beyond  their  angle. 

This  muscle  is  concealed  by  the  rhomboideus  and 
scapula,  except  a  few  of  its  superior  fibres,  which 
appear  above  the  upper  edge  of  the  rhomboideus 
minor.  It  covers  part  of  the  origin  of  the  splenius. 

Use:  To  elevate  the  ribs,  and  dilate  the  thorax. 

Reflect  it  from  the  spine. 

7.  The  SPLENIUS  is  divided  into  two  portions: 

(1.)  The  Splenius  Capitis — Jlrises,  tendinous,  from 
the  spinous  processes  of  the  two  superior  dorsal,  and 
five  inferior  cervical  vertebrae.  It  forms  a  flat  broad 
muscle,  which  ascends  obliquely,  and  is  inserted,  ten- 
dinous, into  the  posterior  part  of  the  mastoid  process, 
and  into  a  small  part  of  the  os  occipitis,  immediately 
below  its  superior  transverse  ridge. 

This  muscle  is  covered  by  the  trapezius^  and  by  the 
insertion  of  the  sterno-cleido-mastoideus,  and  a  small 
part  of  it  is  seen  on  the  side  of  the  neck  betwixt  those 
two  muscles.  The  lower  part  of  its  origin  is  covered 
by  the  serratus  superior  posticus. 

Reflect  it  from  the  occiput. 

(2.)  The  Splenius  Colli— *#mes,  tendinous,  from  the 
spinous  processes  of  the  third,  fourth,  fifth,  and  some- 
times the  sixth  dorsal  vertebrae.  It  forms  a  small 
fleshy  belly,  which  ascends  by  the  side  of  the  verte- 
brae, and  is  inserted  into  the  transverse  processes  of 
the  four  or  five  superior  cervical  vertebrae,  by  distinct 
tendons,  which  lie  behind  similar  tendons  of  the  leva- 
tor  scapulas. 

This  muscle  is  concealed  by  the  serratus  superior 
posticus,  and  splenius  capitis. 

Use:  To  bring  the  head  and  upper  vertebras  of  the 
neck  obliquely  backwards.  When  both  muscles  act, 
they  pull  the  head  directly  backwards. 

Reflect  it  from  the  dorsal  vertebrae. 


GUIDE    TO    ANATOMY.  155 

8.  The  SERRATUS  POSTICUS  INFERIOR — «/2mes,by 
a  broad  thin  tendon,  from  the  spinous  processes  of  the 
two  or  three  inferior  dorsal  vertebrae,  and  from  the 
three  superior  lumbar  spines  by  the  fascia  lumborum. 
Inserted,  by  distinct  fleshy  slips,  into  the  lower 
edges  of  the  four  inferior  ribs,  at  a  little  distance  from 
their  cartilages. 

This  is  a  thin  muscle,  of  considerable  breadth, 
situated  at  the  lower  part  of  the  back,  under  the 
middle  of  the  latissimus  dorsi. 

Use:  To  pull  the  ribs  downwards  and  backwards. 
Reflecting  it  from  the  spine,  you  expose  the  Fascia 
Lumborum.  It  is  a  tendinous  fascia,  arising  from  the 
lumbar  vertebras  and  os  sacrum,  giving  origin  to  the 
lower  part  of  the  serratus  posticus  inferior,  and  to  the 
posterior  fibres  of  the  obliquus  internus  and  transver- 
salis  abdominis.  It  is  also  connected  with  the  tendon 
of  the  latissimus  dorsi. 

On  detaching  from  the  spine,  this  fascia,  and  the 
serratus  posticus  inferior,  we  expose  a  thick  muscular 
mass,  filling  up  all  the  space  betwixt  the  spinous  pro- 
cesses of  the  vertebrae,  and  the  angles  of  the  ribs. 
This  mass  consists  of  three  muscles: 

The  Sacro-Lumbalis  on  the  outside,  the  Longissi- 
mus  Dorsi  in  the  middle,  and  the  Spinalis  Dorsi  close 
to  the  spinous  processes. 

These  three  muscles  are  closely  connected  together; 
so  that,  to  effect  their  separation,  it  is  necessary  to 
divide  some  of  the  fibres. 

9  and  10.  The  SACRO-LUMBALIS  and  LONGISSIMUS 
DORSI — Arise,  by  one  common  origin,  tendinous 
externally,  and  fleshy  internally,  from  the  spinous 
processes  and  posterior  surface  of  the  os  sacrum;  from 
the  posterior  part  of  the  spine  of  the  os  ilium;  from 
the  spinous  processes,  and  from  the  roots  of  the 
transverse  processes  of  all  the  lumbar  vertebrae. 
The  thick  fleshy  belly,  formed  by  this  extensive 


156  LONDON    DISSECTOR,  OR 

origin,  ascends,  and^  opposite  to  the  last  rib,  divides 
into  the  two  muscles. 

The  sacro-lumbalis  is  inserted  into  all  the  ribs  near 
their  angles,  by  long  and  thin  tendons.  The  tendons 
which  pass  to  the  superior  ribs,  are  longer,  ascend  in 
nearly  a  straight  line,  and  are  situated  nearer  to  the 
spine  than  those  which  pass  to  the  lower  ribs.  On 
separating  the  inner  edge  of  this  muscle  (i.  e.  the  edge 
next  to  the  spine)  from  the  latissimus  dorsi,  and  turn- 
ing the  belly  towards  the  ribs,  we  see  six  or  eight  small 
tendinous  and  fleshy  bundles,  which  pass  from  the 
inner  side  of  this  muscle,  to  be  inserted  into  the  upper 
edge  of  the  six  or  eight  inferior  ribs.  These  are  called 
the  Musculi  Accessorii  ad  Sacro-Lumbalem. 

Use:  To  pull  the  ribs  downwards,  to  assist  in  erect- 
ing the  trunk  of  the  body,  and  in  turning  it  to  one  side. 

The  longissimus  dorsi  is  inserted  into  all  the  ribs 
except  the  two  inferior,  betwixt  their  tubercles 
and  angles,  by  slips  which  are  tendinous  and  fleshy, 
and  into  the  transverse  processes  of  all  the  dorsal 
vertebrae  by  small  double  tendons.  The  insertions  in 
the  ribs  proceed  from  the  outer  side  of  the  muscle, 
while  the  attachments  to  the  transverse  processes  are 
seen  on  separating  the  longissimus  dorsi  from  the  spi- 
nalis  dorsi. 

Use:  To  extend  the  vertebrae,  and  keep  the  body 
erect. 

11.  The  SPINALIS  DORSI  is  much  smaller  than  the 
last  two  muscles;  below,  it  cannot  be  separated  from 
the  longissimus  dorsi,  without  dividing  some  fibres;  it 
lies  betwixt  that  muscle  and  the  spine. 

Arises,  tendinous,  from  the  spinous  processes  of  the 
two  superior  lumbar  vertebrae,  and  of  the  three  inferior 
dorsal. 

Inserted  into  the  spinous  processes  of  the  vertebrae 
of  the  back,  from  the  second  to  the  ninth,  by  as  many 
distinct  tendons. 


GUIDE    TO    ANATOMY.  157 

Use:  To  extend  the  vertebrae,  and  to  assist  in 
raising  the  spine. 

The  three  last  described  muscles  are  covered 
below  by  the  serratus  posticus  inferior  and  the  latis- 
simus  dorsi;  above,  by  the  rhomboideus,  serratus 
superior  posticus,  and  trapezius. 

12.  The  CERVICALIS  DESCENDERS — Arises,  from 
the  upper  edge  of  the  four  or  five  superior  ribs,  by  as 
many  distinct  tendons.     It  forms  a  small  belly,  which 
ascends  upwards,  and  is 

Inserted,  by  three  distinct  tendons,  into  the  trans- 
verse processes  of  the  fourth,  fifth,  and  sixth  cervical 
vertebrae,  between  the  splenius  colli  and  levator  scap- 
ulas. This  muscle  is  small,  and  is  frequently  de- 
scribed as  an  appendage  to  the  sacro-lumbalis. 

Use:  To  turn  the  neck  obliquely  backwards. 

13.  The  TRANSVERSALIS  COLLI — Arises  from  the 
transverse  processes  of  the  five  superior  dorsal  verte- 
brae, by  five  tendinous  and  fleshy  slips,  and  is 

Inserted,  tendinous,  into  the  transverse  processes  of 
the  five  or  six  inferior  cervical  vertebrae. 

The  origin  of  this  muscle  lies  on  the  inside  of  the 
longissimus  dorsi,  and  it  is  sometimes  considered  as  an 
appendage  to  it.  The  insertion  is  situated  between  the 
cervicalis  descendens  and  the  trachelo-mastoideus. 

Use:  To  turn  the  neck  obliquely  backwards,  and  a 
little  to  one  side. 

14.  The  TRACHELO-MASTOIDEUS  lies  nearer  to  the 
bone  than  the  last  described  muscle. 

Arises  from  the  transverse  processes  of  the  three 
uppermost  vertebrae  of  the  back,  and  of  the  five 
inferior  of  the  neck,  by  thin  tendons,  which  unite 
and  form  a  fleshy  belly. 

Inserted,  tendinous,  into  the  posterior  surface  of  the 
mastoid  process. 

This  muscle  lies  on  the  outside  of  the  complexus, 
and  on  the  inside  of  the  transversalis  colli;  its  insertion 
14 


158  LONDON    DISSECTOR,  OR 

is  concealed  by  the  splenius  capitis;  it  is  covered  also 
by  the  levator  scapulae. 

Use:  To  keep  the  head  and  neck  erect,  and  to  draw 
the  head  backwards,  and  to  one  side. 

15.  The  COMPLEXUS — Arises,  by  tendinous  and 
fleshy  fibres,  from  the  transverse  processes  of  the 
seven  superior  dorsal,  and  of  the  four  or  five  inferior 
cervical  vertebrae.      It  forms  a  thick,  tendinous,  and 
fleshy  belly. 

Inserted,  tendinous  and  fleshy,  into  the  hollow 
betwixt  the  two  transverse  ridges  of  the  os  occipitis, 
extending  from  the  middle  protuberance  of  that  bone, 
nearly  as  far  as  the  mastoid  process. 

This  is  a  large  muscle.  Its  origin  from  the  cervical 
vertebrae  is  nearer  to  the  spine  than  the  trachelo-mas- 
toideus;  and  in  the  back,  it  arises  nearer  to  the  spine 
than  the  transversalis  colli;  it  is  covered  by  the  sple- 
nius; but  a  large  portion  of  it  is  seen  between  the 
sptenius  and  spine,  immediately  on  removing  the 
trapezius. 

Use:  To  draw  the  head  backwards  and  to  one  side. 

On  removing  the  complexus  from  the  occiput,  we 
find,  close  to  the  spine, 

16.  The  SEMI-SPINALIS  COLLI. — It  arises  by  dis- 
tinct tendons,  from  the  transverse  processes  of  the  six 
superior  dorsal  vertebras,  ascends  obliquely  close  to 
the  spine,  and  is 

Inserted  into  the  spinous  processes  of  all  the  verte- 
brae of  the  neck,  except  the  first  and  last. 

This  muscle  is  situated  close  to  the  vertebrae  at  the 
posterior  part  of  the  neck  and  back.  It  arises  on  the 
outside  of  the  semi-spinalis  dorsi;  its  greater  part  is 
concealed  by  the  complexus  and  longissimus  dorsi; 
and  the  part  which  projects  between  these  muscles, 
is  concealed  by  the  serratus  superior  posticus. 

Use:  To  extend  the  neck  obliquely  backwards. 

17.  SEMI-SPINALIS  DORSI — Arises  from  the  trans- 


GUIDE   TO    ANATOMY.  159 

verse  processes  of  the  seventh,  eighth,  and  ninth  ver- 
tebrae of  the  back,  by  distinct  tendons  which  soon 
grow  fleshy. 

Inserted,  by  distinct  tendons,  into  the  spinous  pro- 
cesses of  the  five  superior  dorsal  vertebrae,  and  of  the 
two  lower  cervical. 

This  muscle  lies  nearer  the  spine  than  the  lower 
part  of  the  semi-spinalis  colli;  its  inferior  origins  lie 
on  the  outside  of  the  insertion  of  the  spinalis  dorsi. 

Use:  To  extend  the  spine  obliquely  backwards. 

The  removal  of  the  complexus  brings  also  into  view 
several  small  muscles,  situated  at  the  superior  part  of 
the  neck,  immediately  below  the  occiput. 

18.  The  RECTUS   CAPITIS  POSTICUS   MAJOR — 
Arises,  fleshy,  from  the  side  of  the  spinous  process  of 
the  dentata.     It  ascends  obliquely  outwards,  becoming 
broader,  and  is 

Inserted,  tendinous  and  fleshy,  into  the  inferior 
transverse  ridge  of  the  os  occipitis,  and  into  part  of 
the  concavity  above  that  ridge. 

Use:  To  extend  and  pull  the  head  backwards,  and 
to  assist  in  its  rotation. 

19.  The    RECTUS   CAPITIS  POSTICUS   MINOR — 
Arises,  tendinous  and  narrow,  from  an  eminence  in  the 
middle  of  the  back  part  of  the  atlas.      It  becomes 
broader,  and  is 

Inserted,  fleshy,  into  the  inferior  transverse  ridge 
of  the  os  occipitis,  and  into  the  surface  betwixt  that 
ridge  and  the  foramen  magnum. 

It  is  partly  covered  by  the  rectus  capitis  posticus 
major;  but  a  large  portion  of  this  pair  of  muscles  is 
seen  projecting  between 'the  recti  majores,  and  is 
situated  beneath  the  complexus. 

Use:  To  draw  the  head  backwards. 

20.  OBLiauus  CAPITIS  SUPERIOR — Arises,  tendi- 
nous, from  the  upper  and  posterior  part  of  the  trans- 
verse process  of  the  first  cervical  vertebra. 


160  LONDON    DISSECTOR,  OR 

Inserted,  tendinous  and  fleshy,  into  the  inferior 
transverse  ridge  of  the  os  occipitis  behind  the  mastoid 
process,  and  into  a  small  part  of  the  surface  above  and 
below  that  ridge. 

Use:  To  draw  the  head  backwards,  and  to  assist 
in  rolling  it. 

21.  OBLIQ.UUS  CAPITIS  INFERIOR — Arises,  from  the 
side  of  the  spinous  process  of  the  dentata,  forms  a  thick 
belly,  and  is 

Inserted  into  the  under  and  back  part  of  the  trans- 
verse process  of  the  atlas. 

Use:  To  rotate  the  head,  by  turning  the  first  ver- 
tebra upon  the  second. 

22.  The  MULTIFIDUS  SPIKE. 

On  removing  the  muscles  of  the  spine  which  have 
been  described,  we  find  situated  beneath  them  the 
Multifidus  Spinae.  It  is  that  mass  of  flesh  which  lies 
close  to  the  spinous  and  transverse  processes  of  the 
vertebrae,  extending  from  the  dentata  to  the  os  sacrum. 
The  bundles  of  which  it  is  composed  seem  to  pass  from 
the  transverse,  to  be  inserted  into  the  spinous  processes. 

Jlrises,  tendinous  and  fleshy,  from  the  spinous  pro- 
cesses and  back  part  of  the  os  sacrum,  and  from  the 
posterior  adjoining  part  of  the  os  ilium;  from  the  ob- 
lique and  transverse  processes  of  all  the  lumbar  verte- 
brae; from  the  transverse  processes  of  all  the  dorsal 
vertebrae;  and  from  those  of  the  cervical  vertebrae, 
excepting  the  first  three.  The  fibres  arising  from  this 
extensive  origin  pass  obliquely,  to  be 

Inserted ,  by  distinct  tendons,  into  the  spinous  pro- 
cesses of  all  the  vertebrae  of  the  loins  and  back  and 
neck,  except  the  atlas.  The  fibres  arising  from  each 
vertebra  are  inserted  into  the  second  one  above  it, 
and  sometimes  more. 

Use:  To  extend  the  back  obliquely,  or  move  it  to 
one  side.  When  both  muscles  act,  they  extend  the 
vertebrae  backwards. 


GUIDE    TO    ANATOMY.  161 

The  small  muscles  situated  between  the  processes 
of  the  vertebrae  are, 

1 .  INTERSPINALES  colli,  dorsi,  et  lumborum.    These 
are  small  bundles  of  fibres,  which  fill  up  the  spaces 
between  the  spinous  processes  of  the  vertebra.    Each 
of  these  little  muscles  arises  from  the  surface  of  one 
spinous  process,  and  is  inserted  into  the  next  spinous 
process. 

In  the  neck  they  are  large,  and  appear  double,  as 
the  spinous  processes  of  the  cervical  vertebrae  are 
bifurcated.  In  the  back  and  loins  they  are  indis- 
tinct, and  are  rather  small  tendons  than  muscles. 

Use:  To  draw  the  spinous  processes  nearer  to  each 
other. 

2.  The  INTERTRANSVERSALIS  colli,  dorsi,  et  lum- 
borum, are  small  muscles  which  fill  up,  in  a  similar 
manner,  the  spaces  between  the  transverse  processes 
of  the  vertebrae.     In  the  neck  they  are  bifurcated  and 
distinct;  in  the  back  they  are  small  and  slender,  and  in 
the  loins  they  are  strong  and  fleshy. 

Use:  To  draw  the  transverse  processes  towards- 
each  other. 


14* 


CHAPTER    XIII. 

DISSECTION  OF  THE  MUSCLES  SITU- 

ATED    BETWEEN   THE  RIBS,  AND 

ON  THE   INNER  SURFACE   OF 

THE    STERNUM. 


THE  muscles  which  fill  up  the  space  between 
the  ribs  are  named  Intercostals;  they  are  disposed  on 
each  side  of  the  thorax  in  two  layers;  and  each  layer 
consists  of  eleven  muscles. 

The  INTERCOSTALES  EXTERNI — Jlrise  from  the 
inferior  acute  edge  of  each  superior  rib,  extending 
from  the  spine  to  near  the  junction  of  the  ribs  with 
their  cartilages.  The  fibres  run  obliquely  forwards 
and  downwards,  and  are 

Inserted  into  the  upper  obtuse  edge  of  each  inferior 
rib,  from  the  spine  to  near  the  cartilage  of  the  rib. 

These  muscles  are  seen  on  removing  the  muscles 
which  cover  the  thorax. 

The  LEVATORES  COSTARUM  are  twelve  small 
muscles,  situated  on  each  side  of  the  dorsal  vertebrae. 
They  are  portions  of  the  external  intercostals.  Each 
of  these  small  muscles  arises  from  the  transverse  pro- 
cess of  one  of  the  dorsal  vertebras,  and  passes  down- 
wards, to  be  inserted  into  the  upper  side  of  the  rib  next 
below  the  vertebra,  near  its  tuberosity. 

The  first  of  these  muscles  passes  from  the  last  cer- 
vical vertebra,  the  eleven  others  from  the  eleven 
superior  dorsal  vertebrae.  The  three  or  four  inferior 
Levatores  are  longer,  and  run  down  to  the  second  rib 


GUIDE   TO    ANATOMY.  163 

below  the  transverse  process  from  which  they  arise. 
Hence  Albinus  names  them  the  Levatores  Costarum, 
Longiores  et  Breviores. 

2.  The  INTERCOSTALES  INTERNI — Jlrise  from  the 
inferior  acute  edge  of  each  superior  rib,  beginning  at 
the  sternum,  and  extending  as  far  as  the  angle  of  the 
rib.  The  fibres  run  obliquely  downwards  and  back- 
wards, and  are 

Inserted  into  the  superior  obtuse  edge  of  each  infe- 
rior rib  from  the  sternum  to  the  angle.  Portions  of 
the  internal  intercostals  pass  over  one  rib,  and  are 
inserted  into  the  next  below  it. 

Thus  the  intercostal  muscles  decussate,  and  are 
double  on  the  sides  of  the  thorax;  but,  from  the  spine 
to  the  angles  of  the  ribs,  there  are  only  the  external 
intercostals,  and,  from  the  cartilages  to  the  sternum, 
only  the  internal,  and  some  cellular  membrane  cover- 
ing them.  The  whole  of  the  internal  intercostals,  and 
the  back  part  of  the  external,  are  lined  by  the  pleura. 

Use:  To  elevate  the  ribs,  by  causing  them  to  approxi- 
mate, and  thus  to  enlarge  the  cavity  of  the  thorax. 

There  is  a  pair  of  muscles  situated  on  the  inner 
surface  of  the  sternum,  viz: 

The  TRIANGULARIS  STERNI,  or  Sterno-Costalis, — 
Arises,  tendinous  and  fleshy,  from  the  edge  of  the 
whole  cartilage  ensiformis,  and  from  the  edge  of  the 
lower  half  of  the  middle  bone  of  the  sternum.  The 
fibres  ascend  obliquely  upwards  and  outwards,  and 
form  a  flat  muscle,  which  is 

Inserted,  by  three  or  four  triangular  fleshy  and  ten- 
dinous terminations,  into  the  cartilages  of  the  third, 
fourth,  fifth,  and  sixth  ribs. 

This  muscle  lies  on  the  inside  of  the  ribs  and  sternum, 
and  is  lined  by  the  pleura. 

Use:  To  depress  the  cartilages  and  the  bony 
extremities  of  the  ribs,  and  consequently  to  assist  in 
lessening  the  cavity  of  the  thorax. 


CHAPTER    XIV. 

DISSECTION     OF     THE     MUSCLES 

SITUATED   ONTHE    ANTERIOR 

PART   OF  THE    NECK,    CLOSE 

TO    THE    VERTEBRA. 


FOUR  pair  of  muscles  are  here  situated. 

1.  The   LONGUS   COLLI — Arises,   tendinous   and 
fleshy,  from  the  sides  of  the  bodies  of  the  three  supe- 
rior dorsal  vertebras,  and  from  the  anterior  surface  of 
the  transverse  processes  of  the  four  or  five  lower 
cervical  vertebras. 

Inserted^  tendinous  and  fleshy,  into  the  fore  part  of 
the  bodies  of  all  the  vertebrae  of  the  neck. 

This  muscle  lies  behind  the  oesophagus,  and  the 
great  vessels  and  nerves  of  the  neck. 

Use:  To  bend  the  neck  forwards,  and  to  one  side. 

2.  The    RECTUS    CAPITIS    INTERNUS  MAJOR — 
Arises,  tendinous  and  fleshy,  from  the  anterior  points 
of  the  transverse  processes  of  the  third,  fourth,  fifth, 
and  sixth  cervical  vertebras.     It  forms  a  considerable 
fleshy  belly. 

Inserted  into  the  cuneiform  process  of  the  os  occip- 
itis  a  little  before  the  condyloid  process. 

This  muscle  lies  before  the  scaleni,  and  more 
outwardly  than  the  longus  colli,  over  part  of  which 
it  passes. 

Use:  To  bend  the  head  forwards. 

3.  The    RECTUS   CAPITIS   INTERNUS   MINOR — 
Arises,  fleshy,  from  the  fore  part  of  the  body  of  the 
atlas,  near  its  transverse  process;    and,  ascending 
obliquely,  is 


GUIDE   TO    ANATOMY.  165 

Inserted  near  the  root  of  the  condyloid  process  of 
the  occipital  bone,  under  the  last  described  muscle. 

Use:  to  bend  the  head  forwards. 

4.  The  RECTUS  CAPITIS  LATERALIS — Arises, 
fleshy,  from  the  anterior  and  upper  part  of  the 
transverse  process  of  the  atlas. 

Inserted,  tendinous  and  fleshy,  into  a  scabrous  ridge 
of  the  os  occipitis,  which  extends  from  the  condyloid 
process  of  that  bone  towards  the  mastoid  process. 

It  is  situated  immediately  behind  the  internal  jugular 
vein,  where  it  comes  out  from  the  cranium. 

Use:  To  pull  the  head  a  little  to  one  side. 

Besides  these  muscles,  we  meet  also  with 

1 .  The  SCALENUS  ANTICUS — Arises,  by  three  ten- 
dons, from  the  transverse  processes  of  the  fourth,  fifth, 
and  sixth  vertebrae  of  the  neck^ 

Inserted,  tendinous  and  fleshy,  into  the  upper  edge 
of  the  first  rib,  near  its  cartilage. 

2.  The  SCALENUS  MEDIUS — Arises,  tendinous,  from 
the  transverse  processes  of  all  the  vertebrae  of  the 
neck. 

Inserted  into  the  upper  and  outer  part  of  the  first 
rib,  from  its  root  to  within  the  distance  of  half  an  inch 
from  the  scalenus  anticus. 

The  nerves  to  the  superior  extremity  pass  between 
this  muscle  and  the  former. 

3.  The   SCALENUS   POSTICUS — Arises,  tendinous, 
from  the  transverse  processes  of  the  fifth  and  sixth 
vertebrae  of  the  neck. 

Inserted  into  the  upper  edge  of  the  second  rib,  near 
the  spine. 

These  muscles  are  covered  before  by  the  sterno- 
mastoideus  and  trapezius,  behind  by  the  trapezius  and 
levator  scapulae;  but  the  scaleni  are  so  connected  with 
the  muscles  of  the  spine,  that  the  whole  of  them  cannot 
be  demonstrated  till  the  muscles  of  the  back  and  neck 
are  dissected. 


166  LONDON    DISSECTOR,  OR 

Use  of  these  three  muscles:  To  bend  the  neck  to 
one  side,  and,  when  the  muscles  of  both  sides  act,  to 
bend  it  forwards;  or,  when  the  neck  is  fixed,  to  elevate 
the  ribs,  and  dilate  the  chest. 

We  have  given  the  description  of  the  three  parts, 
but  it  is  proper  to  remark  that  some  anatomists  of 
eminence  regard  it  as  one  triangular  muscle. 


CHAPTER    XV. 

DISSECTION     OF     THE     SUPERIOR 
EXTREMITY. 


SECTION.    I. 
OF    THE   SHOULDER   AND    ARM. 

IN  the  thigh  we  saw  a  strong  fascia,  arising  from 
the  neighbouring  bones  and  ligaments,  firmly  investing 
the  muscles,  and  giving  origin  to  some  of  their  fibres; 
but,  on  removing  the  integuments  of  the  shoulder  and 
arm,  we  meet  with  no  regular  fascia.  The  muscles, 
like  those  on  the  outside  of  the  thorax,  are  covered 
by  condensed  cellular  substance,  which  might  be  taken 
for  a  thin  aponeurosis;  but  which  is  widely  different 
in  its  nature,  and  ought  to  be  regularly  dissected  off 
with  the  integuments. 

There  are  ten  muscles  situated  on  the  shoulder  and 
the  humerus. 

1.  The  DELTOIDES — «#mes,  tendinous  and  fleshy, 
from  the  posterior  third  of  the  clavicle,  from  the  whole 
edge  of  the  acromion,  and  from  the  lower  margin  of 


GUIDE   TO   ANATOMY.  167 

the  whole  spine  of  the  scapula.  From  these  several 
origins  the  fibres  run  in  different  directions,  and  con- 
verge. Those  arising  from  the  clavicle  run  outwards 
and  downwards:  those  from  the  spine  of  the  scapula 
outwards,  forwards,  and  downwards;  and  those  from 
the  acromion  directly  downwards. 

Inserted,  tendinous,  into  a  triangular  rough  surface 
on  the  outer  side  of  the  os  humeri,  near  its  middle. 

This  muscle  is  entirely  superficial,  except  where 
the  thin  fibres  of  the  platysma  myoides  arise  from  its 
anterior  surface.  It  forms  a  strong  coarse  muscle,  and 
covers  the  whole  of  the  fore  part  and  outside  of  the 
shoulder  joint. 

Use:  To  draw  the  arm  directly  upwards,,  and  to 
move  it  a  little  forwards  or  backwards,  according  to 
the  different  directions  of  its  fibres.  Having  reflected 
this  muscle  from  the  scapula  and  clavicle,  you  will 
expose  more  completely  the  muscles  on  the  dorsum 
of  the  former  bone.  They  fill  up  the  posterior  surface 
of  the  scapula,  and  are  covered  by  a  fascia,  which 
adheres  to  the  spine  and  edges  of  that  bone.  On  dis- 
secting off  this  fascia,  the  fleshy  fibres  of  the  muscles 
will  be  found  arising  from  its  inner  surface. 

2.  The  SUPRA-SPINATUS — Arises,  fleshy,  from  all 
that  part 'of  the  base  of  the  scapula  which  is  above  its 
spine;  from  the  superior  costa  as  far  forwards  as  the 
semilunar  notch;  from  the  spine  itself,  and  from  the 
concave  surface  betwixt  it  and  the  superior  costa. 
The  fleshy  fibres,  as  they  approach  the  neck  of  the 
scapula,  terminate  in  a  tendon  which  passes  under  the 
acromion,  slides  over  the  neck  of  the  scapula  (to  which 
it  is  connected  by  loose  cellular  membrane,)  adheres 
to  the  capsular  ligament  of  the  shoulder-joint,  and  is 

Inserted  into  the  anterior  and  superior  part  of  the 
great  tuberosity  near  the  head  of  the  os  humeri. 
Use:  To  raise  the  arm. 

3.  The  INFRA-SPINATUS,  Mses,  principally  fleshy, 


168  LONDON    DISSECTOR,  OR 

from  the  lower  part  of  the  spine  of  the  scapula 
as  far  back  as  the  triangular  flat  surface;  from  the 
base  of  the  bone  below  the  spine  to  near  the  inferior 
angle;  from  the  posterior  ridge  of  the  inferior  costa; 
and  from  all  the  dorsum  of  the  bpne  below  the  spine. 
The  fibres  ascend  and  descend  towards  a  middle 
tendon,  which  runs  forwards  over  the  neck  of  the 
bone,  and  adheres  to  the  capsular  ligament. 

Inserted,  by  a  strong  short  tendon,  into  the  middle 
part  of  the  great  tuberosity  of  the  os  humeri. 

Use:  To  roll  the  humerus  outwards,  to  assist  in 
raising  the  arm,  and  in  moving  it  outwards  when 
raised. 

4.  The  TERES  MINOR — Jlrises,  fleshy,  from  the 
inferior  costa  of  the  scapula,  extending  from  the  neck 
of  the  bone  to  within  an  inch  or  two  of  the  inferior 
angle.     It  passes  forwards  along  the  inferior  edge  of 
the  infra-spinatus,  adheres  to  the  capsular  ligament  of 
the  shoulder-joint,  and  is 

Inserted^  tendinous  and  fleshy,  into  the  lower  and 
back  part  of  the  great  tuberosity  of  the  os  humeri. 

Use:  To  draw  the  humerus  downwards  and  back- 
wards, and  to  roll  it  outwards. 

5.  The  TERES  MAJOR — Arises^  from  an  oblong, 
rough,  flattened  surface,  at  the  inferior  angle  of  the 
scapula.     It  forms  a  thick  belly,  which  passes  for- 
wards and  upwards  towards  the  inside  of  the  arm. 

Inserted^  by  a  broad  thin  tendon,  into  the  ridge  of 
the  os  humeri,  at  the  inner  side  of  the  groove  for 
lodging  the  tendon  of  the  long  head  of  the  biceps 
flexor  cubiti;  its  tendon  is  inserted  along  with  the 
tendon  of  the  latissimus  dorsi. 

Use:  To  roll  the  humerus  inwards,  and  to  draw  it 
backwards  and  downwards. 

6.  The  SUBSCAPULARIS — Arises,  fleshy,  from  all 
the  base  of  the  scapula  internally;  from  the  superior 
and  inferior  costae;  and  from  the  whole  internal  surface 


GUIDE    TO    ANATOMY.  169 

of  the  bone.  It  consists  of  tendinous  and  fleshy  bun- 
dles, which  converge,  slide  over  the  inner  surface  of 
the  neck  of  the  scapula,  pass  in  the  hollow  under  the 
root  of  the  coracoid  process,  and  adhere  to  the  inner 
part  of  the  capsular  ligament  of  the  shoulder  joint. 

Inserted,  by  a  strong  tendon,  into  the  less  tuberosity 
near  the  head  of  the  os  humeri. 

The  whole  of  this  muscle  is  concealed  by  the  scapula 
and  muscles  of  the  shoulder.  It  lies  betwixt  that  bone 
and  the  serratus  magnus. 

Use:  To  roll  the  os  humeri  inwards,  and  to  draw  it 
to  the  side  of  the  body. 

7.  The  BICEPS  FLEXOR  CUBITI — Arises  by  two 
heads.  The  first  and  outermost,  called  the  Long 
Head,  arises,  by  a  strong  tendon,  from  a  smooth  sur- 
face in  the  upper  edge  of  the  glenoid  cavity  of  the 
scapula.  It  passes  over  the  head  of  the  os  humeri, 
within  the  capsular  ligament  of  the  shoulder-joint,  and 
enters  a  groove  betwixt  the  two  tuberosities  of  that 
bone.  It  forms  a  strong  fleshy  belly.  The  second 
and  innermost,  called  the  Short  Head,  arises,  tendi- 
nous, from  the  lower  part  of  the  coracoid  process  of 
the  scapula,  in  common  with  the  coraco-brachialis, 
and  sends  off  a  fleshy  belly. 

These  two  fleshy  bellies  are  at  first  only  connected 
by  condensed  cellular  membrane.  They  form  a  thick 
mass,  and,  below  the  middle  of  the  arm,  become  in- 
separably united.  They  send  off  a  strong  tendon, 
which  is  at  first  broad,  but  soon  becomes  rounder,  and 
passes  over  the  fore  part  of  the  elbow-joint.  It  then 
slides  over  the  cartilaginous  middle  surface  of  the 
tubercle  at  the  upper  end  of  the  radius,  and  is 

Inserted  into  the  posterior  and  internal  rough  part 
of  that  tubercle;  and  by  a  lateral  slip  of  fascia  into  the 
sheath  of  the  fore  arm. 

The  belly  of  the  muscle  is  immediately  under  the 
15 


170  LONDON    DISSECTOR,  OR 

integuments,  and  so  is  the  tendon  where  it  passes  over 
the  elbow-joint. 

Use:  To  turn  the  hand  supine,  to  bend  the  fore-arm 
on  the  arm,  and  the  arm  on  the  shoulder. 

8.  The  CORACO  BRACHIALIS — Arises,  tendinous  and 
fleshy,  from  the  middle  part  of  the  apex  of  the  cora- 
coid  process  of  the  scapula.    Its  fibres,  as  it  descends, 
also  arise  from  the  edge  of  the  short  tendon  of  the  bi- 
ceps flexor  cubiti.     It  forms  a  flat  fleshy  belly  which 
is  always  perforated  by  the  nerve,  named  Musculo- 
Cutaneus. 

Inserted,  tendinous  and  fleshy,  about  the  middle  of 
the  internal  part  of  the  os  humeri,  into  a  rough  ridge. 
Use:  To  move  the  arm  upwards  and  forwards. 

9.  The   BRACHIALIS  INTERNUS — Arises  from  the 
middle  of  the  os  humeri,  by  two  fleshy  slips,  which 
pass  on  each  side  of  the  insertion  of  the  deltoid  muscle; 
fleshy  from  all  the  fore  part  of  the  bone  below,  nearly 
as  far  as  the  condyles.    The  fibres  converge,  pass  over 
the  elbow-joint,  and  adhere  to  the  capsular  ligament. 

Inserted,  by  a  strong  short  tendon,  into  the  rough 
surface  immediately  below  the  coronoid  process  of 
the  ulna. 

Use:  To  bend  the  fore-arm. 

10.  The  TRICEPS  EXTENSOR  CUBITI  is  the  great 
muscle  which  covers  all  the  back  part  of  the  arm.     It 
arises  by  three  heads.      The  first,  or  long  head,  by  a 
broad  tendon,  from  the  inferior  costa  of  the  scapula 
near  its  cervix;  this  forms  a  large  belly,  wrhich  covers 
the  back  part  of  the  os  humeri.     The  second,  or  short 
head,  arises,  on  the  outer  and  back  part  of  the  os  hu- 
meri, from  a  ridge  which  runs  from  the  back  part  of 
the  great  tuberosity  towards  the  outer  condyle.     The 
third  head,  called  BRACHIALIS  EXTERNUS,  arises  by 
an  acute  beginning,  from  the  inside  of  the  os  humeri 
above  its  middle,  and  from  a  ridge  extending  to  the 
inner  condyle. 


GUIDE    TO    ANATOMY.  171 

The  three  heads  unite  above  the  middle  of  the  os 
humeri,  and  invest  the  whole  back  part  of  the  bone. 
They  form  a  thick  strong  tendon,  which  is 

Inserted  into  the  Olecranon,  and  partly  into  the 
condyles  of  the  os  humeri,  adhering  firmly  to  the  cap- 
sular  ligament. 

The  tendon  of  the  triceps  sends  off  a  thin  fascia, 
which  covers  the  triangular  surface  of  the  ulna,  on 
which  we  commonly  lean.  Numerous  fibres  are  also 
sent  off  to  assist  in  forming  the  fascia  of  the  fore-arm. 

Use:  To  extend  the  fore-arm.  The  long  head  will 
also  assist  in  drawing  the  arm  backwards. 

The  ANCONEUS  is  a  small  triangular  muscle,  situated 
at  the  outer  side  of  the  olecranon,  immediately  under  • 
the  integuments. 

It  arises,  tendinous,  from  the  posterior  and  lower 
part  of  the  external  condyle  of  the  os  humeri;  forms  a 
thick  triangular  fleshy  mass,  adhering  to  the  capsular 
ligament  of  the  elbow-joint,  and  is 

Inserted  into  the  concave  surface  on  the  outside  of 
the  olecranon,  and  into  the  posterior  edge  of  the  ulna, 

This  muscle  lies  betwixt  the  upper  part  of  the  ex- 
tensor carpi  ulnaris  and  the  olecranon.  It  is  partly 
covered  by  the  tendon  of  the  triceps  extensor  cubiti, 
and  is  enveloped  in  a  fascia  sent  off  from  that  tendon. 

Use:  To  assist  in  extending  the  fore-arm, 


SECTION    II. 

DISSECTION    OF    THE    FASCIA    AND  MUSCLES  SITUATED 
ON    THE    CUBIT    OR    FORE    ARM.* 

ON  removing  the  integuments  of  the  fore-arm,  we 
find,  as  in  the  leg,  a  strong  fascia  investing  all  the 

*  In  the  following  description,  the  palm  of  the  hand  is  supposed  to  be 
turned  forwards,  so  that  the  radius  and  thumb  are  upon  the  outer  *ide 
of  the  fore- arm,  and  the  ulna  and  little  finger  upon  its  inner  side. 


172  LONDON    DISSECTOR,  OR 

muscles.  This  fascia  is  continued  from  the  intermus- 
cular  ligaments  which  pass  down  to  the  condyles  of 
the  os  humeri.  It  is  attached  to  the  condyles,  and 
adheres  firmly  to  the  olecranon  of  the  ulna.  On  the 
posterior  part,  it  receives  a  great  addition  of  fibres 
from  the  tendon  of  the  triceps  extensor;  and  on  the 
fore-part  of  the  arm,  it  appears  to  be  a  continuation 
of  the  aponeurosis  which  is  sent  off  from  the  biceps 
flexor  cubiti. 

Above  the  fascia,  we  meet  with  several  cutaneous 
veins  and  nerves. 

The  dissection  of  the  fascia  of  the  fore-arm  is  simi- 
lar to  that  of  the  fascia  of  the  leg.  It  is  found  firmly 
attached  to  the  fibres  of  the  muscles,  so  that  the  ex- 
posed surface  appears  ragged.  Between  the  muscles 
it  sends  down  Ligaments  called  Intermuscular,  which 
connect  the  muscles,  and  give  origin  to  many  of  their 
fibres. 

General  Observations. — In  dissecting  the  fore-arm, 
you  will  not  expect  to  find  each  muscle  separate  from 
the  contiguous  ones,  as  far  as  its  very  origin  from  the 
bones.  The  partitions  of  fascia  unite  them  most  firmly 
to  a  considerable  distance  from  their  commencement; 
and  these  connections  should  not  be  disturbed,  since 
they  are  as  justly  to  be  regarded  in  the  light  of  origins 
of  the  muscles,  as  the  attachments  which  the  fibres 
have  to  the  bone.  The  muscles  are  divided  into  two 
masses;  of  which  one  lies  over  the  radius  and  back  of 
the  fore-arm,  and  contains  the  supinators  and  exten- 
sors: the  other,  situated  over  the  ulna,  and  inner  side 
of  the  fore-arm,  consists  of  the  pronators  and  flexors. 
Although  some  muscles  in  each  of  these  masses  arise 
quite  separately,  others  are  joined  into  a  common  ten- 
dinous and  fleshy  origin,  in  the  manner  just  described. 
First  then,  clean  all  the  muscles  as  they  lie;  and'  after 
observing  them  in  their  relative  position,  reflect  each 
muscle,  beginning  with  the  superficial  ones,  and  read 
its  description  at  the  same  time. 


GUIDE    TO    ANAT03IY.  173 

The  student  may  perhaps  remember  the  muscles 
more  readily,  by  arranging  them  in  classes  of  three 
each;  thus: 

For  the  motion  of  the  wrist,  three  flexors,  the  ulnaris, 
radialis,  and  medius,  commonly  called  palmaris  lon- 
gus.  Three  extensors,  ulnaris,  radialis  longior,  and 
brevior.  Three  pronators,  the  teres,  quadratus,  and 
the  mass  of  flexor  muscles.  Three  supinators,  the 
supinator  longus,  brevis,  and  biceps  cubiti.  There 
are  three  extensors  of  the  fingers,  extensor  communis 
digitorum,  extensor  primi  digiti,  extensor  minimi 
digiti.  Three  extensors  of  the  thumb,  extensor  primus, 
secundus,  and  tertius.  Three  flexors  of  the  fingers  and 
thumb,  flexor  digitorum  sublimis,  flexor  digitorum  pro- 
fundus,  flexor  pollicis  longus. 

MUSCLES     SITUATED     ON    THE     FORE    PART     OF    THE 

CUBIT,     AND    ARISING    FROM     THE    INNER    CON- 

DYLE    OF   THE    OS    HUMERI. 

These  are  eight  in  number,  and  may  be  divided^ 
into  two  classes:  the  superficial,  and  the  deep-seated. 

First,  the  superficial. 

All  the  muscles  passing  from  the  inner  condyle 
may  be  said  to  arise  by  one  common  tendinous  head; 
but  they  will  be  here  described  as  arising  distinct 
from  the  condyle.  It  must,  however,  be  recollected, 
that  their  origins  are  intimately  connected  by  inter- 
muscular  ligaments,  and  that  they  cannot  be  separated 
without  dividing  some  of  their  fibres. 

1.  The  PRONATOR  RADII  TERES — Arises,  tendi- 
nous and  ileshy,  from  the  anterior  surface  of  the  inner 
condyle  of  the  os  humeri,  and  from  the  coronoid  pro- 
cess of  the  ulna,  and  the  fascia  of  the  fore  arm.  The 
fibres  pass  outwards,  run  by^the  side  of  the  tubercle 
of  the  radius,  and  pass  over  the  outer  edge  of  that 
bone,  to  be 
15* 


174  LONDON    DISSECTOR,  OR 

Inserted,  tendinous  and  fleshy,  into  a  rough  surface 
on  the  back  part  of  the  radius  about  its  middle. 

Its  tendon,  to  arrive  at  its  place  of  insertion,  passes 
under  the  belly  of  the  supinator  longus,  and,  when 
that  muscle  is  removed,  will  be  found  inserted  into 
the  radius  immediately  below  the  supinator  brevis. 

Use:  To  roll  the  radius,  together  with  the  hand, 
inwards. 

2.  The  FLEXOR  CARPI  RADIALIS — Arises,  from 
the  lower  and  fore  part  of  the  internal  condyle  of  the 
os  humeri;  fleshy  from  the  fascia  and  intermuscular 
ligaments,  and  from  the  upper  end  of  the  ulna.     It 
forms  a1  thick  belly,  which  runs  down  the  fore  arm, 
and  terminates  in  a  flat  tendon,     This  tendon  passes 
under  the  annular  ligament*  of  the  wrist,  runs  through 
a  groove  in  the  os  trapezium,  and  is 

Inserted  into  the  fore  part  of  the  base  of  the  meta- 
carpal  bone  sustaining  the  fore  finger. 

Its  insertion  cannot  be  seen  till  the  palm  of  the  hand 
is  dissected,  where  it  will  be  found  concealed  by  the 
muscles  of  the  ball  of  the  thumb. 

Use:  To  bend  the  hand,  and  to  assist  in  its  prona- 
tion. 

3.  The  PALMARIS  LONGUS — Arises,  by  a  slender 
tendon,  from  the  fore  part  of  the  inner  condyle  of  the 
os  humeri;  and  fleshy,  from  the  intermuscular  liga- 
ments; it  forms  a  short  fleshy  belly,  which  soon  sends 
off  a  long  slender  tendon.   This  tendon  descends  along 
the  fore  arm,  and  is 

*  The  annular  ligament  of  the  wrist  consists  of  two  parts.  1.  The 
ligamentum  carpi  transyersale  externum  passes  from  the  styloid  process 
of  the  ulna  and  os  pisiforme,  transversely,  over  the  back  of  the  wrist, 
and  spreads  out  broad,  to  be  affixed  to  the  styloid  process  of  the  radius. 
Under  it  pass  the  tendons  of  the  extensor  muscles.  2.  The  ligamentum 
carpi  transversale  internum  is  a  strong  ligament,  which  passes  across  the 
fore  part  of  the  wrist.  It  arises -from  the  os  pisiforme  and  os  unciforme 
on  the  inner  edge  of  the  wrist,  and  is  attached  to  the  os  scaphoides  and 
os  trapezium  on  the  outer  edge.  Under  it  pass  the  tendons  of  the  flexor 
muscles. 


GUIDE    TO    ANATOMY.  175 

Inserted,  near  the  root  of  the  thumb,  into  the  annular 
ligament  of  the  wrist,  and  into  a  tendinous  mem- 
brane that  covers  the  palm  of  the  hand,  named  Fascia, 
or  Aponeurosis  Palmaris. 

It  arises  betwixt  the  flexor  carpi  radialis  and  flexor 
ulnaris.  Its  tendon  descends  between  these  two 
muscles,  and  above  the  fibres  of  the  flexor  digitorum 
sublimis.  This  muscle  is  sometimes  wanting. 

Use:  To  bend  the  hand,  and  to  stretch  the  palmar 
aponeurosis. 

4.  The  FLEXOR  CARPI  ULNARIS — Arises,  from  the 
inferior  part  of  the  internal  condyle  of  the  os  humeri; 
tendinous  and  fleshy,  from  the  inner  side  of  the  olec- 
ranon,  and  by  a  tendinous  expansion  from  the  posterior 
ridge*  of  the  ulna,  to  nearly  the  lower  end  of  the  bone; 
and  from  the  intermuscular  ligaments  and  fascia  of 
the  fore-arm.      The  fibres  pass  obliquely  forwards 
into  a  tendon  which  runs  over  the  fore-part  of  the 
ulna,  and  is 

Inserted  into  the  os  pisiforme,  and  sometimes  sends 
its  fibres  over  a  small  ligament  which  goes  to  the  base 
of  the  metacarpal  bone  of  the  little  finger. 

The  tendon  is  bound  down  by  a  thin  aponeurotic 
slip,  which  passes  from  the  inner  part  of  the  annular 
ligament  of  the  wrist. 

Use:  To  bend  the  hand. 

5.  The  FLEXOR  SUBLIMIS  PERFORATUS — Arises, 
tendinous  and  fleshy;  from  the  under  part  of  the  inter- 
nal condyle  of  the  os  humeri;  tendinous,  from   the 
lower  part  of  the  coronoid  process  of  the  ulna;  fleshy, 
from  the  tubercle  of  the  radius,  from  the  middle  of 
the  fore  part  of  that  bone,  and  from  the  middle  third 
of  its  outer  edge.    These  origins  form  a  strong  fleshy 
mass,  which  sends  off  four  tendons.    The  tendons  are 
connected  by  cellular  membrane,  and  pass  together 

*  The  ridge  which  leads  to  the  styloid  process. 


176 

under  the  annular  ligament  of  the  wrist;  after  which 
they  separate,  become  thinner  and  flatter,  pass  along 
the  metacarpal  bone  and  first  phalanx  of  each  of  the 
fingers,  and  are 

Inserted  into  the  anterior  and  upper  part  of  the 
second  phalanx,  each  tendon  being,  near  the  extrem- 
ity of  the  first  phalanx,  divided  for  the  passage  of  a 
tendon  of  the  flexor  profundus. 

To  expose  the  origin  of  this  muscle,  the  bellies  of 
the  pronator  teres,  flexor  carpi  radialis,  and  palmaris 
longus,  must  be  detached  from  the  condyle. 

Its  tendons  will  be  seen  in  the  dissection  of  the 
palm  of  the  hand. 

Use:  To  bend  the  second  joint  or  phalanx  of  the 
fingers. 

By  removing  the  belly  of  the  flexor  sublimis,  we 
expose  the  deep  seated  muscles. 

6.  The  FLEXOR  PROFUNDUS  PERFORANS — Jlrises^ 
fleshy,  from  the  smooth  concavity  on  the  inside  of  the 
ulna,  between  the  coronoid  process  and  the  olecranon; 
from  the  smooth  flat  surface  of  the  ulna,  betwixt  its 
posterior  and  internal  angles;  from  the  under  part  of 
the  coronoid  process;  from  the  fore  part  of  the  ulna 
below  that  process,  and  from  the  inner  half  of  the  in- 
terosseous  ligament.    This  muscle  forms  a  thick  mass, 
which  descends  along  the  fore  part  of  the  ulna,  ad- 
hering to  that  bone  as  low  as  one-third  of  its  length 
from  its  inferior  extremity,  and  terminates  in  sending 
off  four  tendons.    These  tendons  are  flat,  pass  together 
under  the  annular  ligament  of  the  wrist,  run  through 
the  slits  in  the  tendons  of  the  flexor  sublimis,  and  are 

Inserted  into  the  fore  and  upper  part  of  the  third  or 
last  phalanx  of  all  the  fingers. 

Use:  To  bend  the  last  joint  of  the  fingers. 

7.  FLEXOR    LONGUS   POLLICIS    MANUS — Arises, 
from  the  upper  "and  fore  part  of  the  radius,  immedi- 
ately below  its  tubercle,  fleshy,  from  the  outer  edge 


GUIDE    TO    ANATOMY.  177 

and  anterior  surface  of  that  bone  as  low  as  two  inches 
above  its  inferior  extremity,  and  from  the  outer  part 
of  the  interosseous  ligament.  It  has  also  generally  a 
tendinous  origin  from  the  internal  condyle  of  the  os 
humeri.  The  tendon  of  the  muscle  passes  under  the 
annular  ligament  of  the  wrist,  and  is 

Inserted  into  the  last  bone  of  the  thumb. 

Use:  To  bend  the  last  joint  of  the  thumb. 

On  separating  the  lower  part  of  the  two  last  de- 
scribed muscles,  we  expose  a  small  square  muscle, 
passing  transversely  just  above  the  wrist,  and  lying 
close  to  the  bones. 

8.  The  PRONATOR  QUADRATUS — Arises,  broad, 
tendinous,  and  fleshy,  from  the  inner  edge  of  the  ulna, 
extending  from  the  lower  extremity  of  the  bone  two 
inches  up  its  edge.  The  fibres  run  transversely, 
adhere  to  the  interosseous  ligament,  and  are 

Inserted  into  the  lower  and  anterior  part  of  the 
radius. 

Use:  To  turn  the  radius,  together  with  the  hand, 
inwards. 

MUSCLES  SITUATED  ON  THE  OUTER  AND  BACK  PART  OF 
THE     FORE-ARM,     AND     ARISING     FROM     THE 
OUTER  CONDYLE  OF  THE  OS  HUMERI. 

These  muscles  are  eleven  in  number,  and  may  be 
divided  into  two  classes:  the  superficial,  and  the 
deep  seated. 

THE    SUPERFICIAL. 

The  muscles  which  arise  from  the  outer  condyle 
are  much  more  distinct  in  their  origins  than  those  from 
the  inner.  Several  of  them  arise  a  considerable  way 
up  the  os  humeri;  but  there  is  here  also  a  common 
tendinous  origin,  from  which  the  extensor  carpi  radia- 
lis  brevior,  extensor  digitorum  communis,  and  exten- 


178  LONDON    DISSECTOR,  OR 

sor  carpi  radialis,  proceed;  so  that  these  muscles  are 
intimately  connected. 

1.  SUPINATOR  RADII  LONGUS — Arises )  tendinous 
and  fleshy,  from  the  external  ridge  of  the  os  humeri, 
nearly  as  far  up  as  the  middle  of  the  bone,  and  ceases 
to  adhere  about  two  inches  above  the  condyle.     It 
forms  a  thick  fleshy  belly,  which  passes  over  the  side 
of  the  elbow-joint,  becomes  smaller,  and  terminates 
above  the  middle  of  the  fore-arm  in  a  flat  tendon. 
The  tendon  becomes  gradually  rounder,  and  is 

Inserted  into  the  lower  end  of  the  radius  on  its 
outer  side. 

This  muscle  is  situated  immediately  under  the 
integuments  along  the  outer  edge  of  the  arm  and  fore- 
arm; and  its  insertion  is  crossed  by  the  extensors  of 
the  thumb. 

Use:  To  roll  the  radius  outwards,  and  turn  the 
palm  of  the  hand  upwards;  also  to  bend  the  fore-arm 
on  the  humerus. 

2.  The  EXTENSOR  CARPI  RADIALIS  LONGIOR — 
Arises,  tendinous  and  fleshy,  from  the  external  ridge 
of  the  os  humeri,  beginning  immediately  below  the 
origin  of  the  supinator  longus,  and  continuing  to  arise 
as  far  as  the  upper  part  of  the  outer  condyle.     It 
forms  a  thick  short  belly,  which  passes  over  the  side 
of  the  elbow-joint,  and  terminates  above  the  middle 
of  the  radius  in  a  flat  tendon.     This   tendon  runs 
along   the    radius,   and,   becoming   rounder,   passes 
through  a  groove  in  the  back  part  of  the  inferior 
extremity  of  that  bone,  to  be 

Inserted  into  the  posterior  and  upper  part  of  the 
metacarpal  bone  of  the  fore-finger. 

Use:  To  extend  the  wrist,  and  move  the  hand 
backwards,  and  to  assist  in  bending  the  fore-arm. 

3.  The  EXTENSOR  CARPI  RADIALI*  BREVIOR-— 
Arises,  tendinous,  from  the  under  and  back  part  of 
the  external  condyle  of  the  os  humeri,  and  from  the 


GUIDE    TO    ANATOMY.  179 

external  lateral  ligament  of  the  elbow-joint.  Its  thick 
belly  runs  along  the  outside  of  the  radius,  and  termi- 
nates in  a  tendon,  which  passes  through  the  same 
groove  in  the  radius  as  the  extensor  radialis  longior, 
and  under  the  annular  ligament. 

Inserted,  by  a  round  tendon,  into  the  upper  and 
back  part  of  the  metacarpal  bone  that  supports  the 
middle  finger. 

Use:  To  extend  the  hand. 

4.  The  EXTENSOR  DIGITORUM  COMMUNIS  -  -Arises, 
tendinous,  from  the  under  part  of  the  external  con- 
dyle  of  the  os  humeri;  fleshy,  from  the  n',ermuscular 
ligaments   which  connect  it  to   the   extensor   carpi 
radialis  brevior  before,  and  the  extensor  carpi  ulnaris 
behind,  and  from  the  inner  surface  of  the  fascia.     It 
descends  along  the  back  part  of  the  fore-arm,  and 
adheres  to  the  ulna  where  it  passes  over  it.     The 
fleshy  belly  terminates  in  four  flat  tendons,  which 
pass  under  the  annular  ligament  in  a  depression  on  the 
back  part  of  the  radius,  and  are 

Inserted  into  the  posterior  part  of  all  the  bones  of 
the  fingers  by  a  tendinous  expansion. 

The  tendons  are  connected  on  the  back  of  the 
metacarpal  bone  by  cross  slips.  The  inner  part  of 
this  muscle  is  sometimes  described  as  a  separate 
muscle,  and  is  called  Extensor  Proprius  Minimi  Digiti, 
vel  Auricularis.  It  passes  through  a  separate  depres- 
sion of  the  radius,  and  a  particular  ring  of  the  annu- 
lar ligament. 

Use:  To  extend  all  the  joints  of  the  fingers. 

The  posterior  surface  of  each  finger  is  covered  with 
a  tendinous  expansion  which  is  formed  by  the  tendons 
of  the  common  extensor,  of  the  lumbricales,  and 
interossei.  This  tendinous  expansion  terminates  in 
the  third  or  extreme  phalanx. 

5.  The  EXTENSOR  CARPI  ULNARIS — Arises^  tendi- 
nous, from  the  under  part  of  the  external  condyle; 


180  LONDON    DISSECTOR,  OR 

fleshy,  from  the  inter  muscular  ligaments  and  inside  of 
the  fascia.  It  crosses  towards  the  ulna,  and  arises, 
fleshy,  from  the  back  part  of  that  bone.  It  termi- 
nates in  a  strong  tendon,  which  passes  through  a 
groove  in  the  back  part  of  the  lower  end  of  the  ulna, 
under  the  annular  ligament,  and  is 

Inserted  into  the  posterior  and  upper  part  of  the 
metacarpal  bone  of  the  little  finger. 

This  muscle  is  entirely  superficial,  and  serves  to 
extend  the  wrist,  and  bring  the  hand  backwards;  but 
chiefly  to  bend  the  hand  laterally  towards  the  ulna. 
The  next  muscle^would  be  the  anconeus,  but  that  has 
been  already  described. 

By  removing  the  superficial  muscles,  we  expose 

THE    DEEP  SEATED. 

6.  The  SUPINATOR  RADII  BREVIS — Arises ,  tendi- 
nous, from  the  lower  part  of  the  external  condyle  of 
the  os  humeri;  from  the  outer  surface  of  the  ulna;  and 
from  the  interosseous  ligament:  it  passes  outwards 
round  the  upper  part  of  the  radius,  and  is 

hiserted  into  the  upper  and  outer  edge  of  the  tuber- 
cle of  the  radius,  and  into  an  oblique  ridge  extending 
from  the  tubercle  downwards  and  outwards  to  the 
insertion  of  the  pronator  teres. 

This  muscle  nearly  surrounds  the  upper  and  outer 
part  of  the  radius. 

Use:  To  roll  the  radius  outwards,  and  bring  the 
hand  supine. 

On  the  back  p^art  of  the  fore  arm  we  meet  with 
three  muscles  going  to  the  thumb,  and  one  to  the  fore 
finger. 

7.  The  EXTENSOR  Ossis  METACARPI  POLLICIS — 
Arises,  fleshy,  from  the  middle  and  posterior  part  of 
the  ulna,  immediately  below  the  termination  of  the 
anconeus,  from  the  interosseous  ligament,  and  from 


GUIDE    TO    ANATOMY.  181 

the  posterior  surface  of  the  radius  below  the  insertion 
of  the  supinator  radii  brevis.  The  fleshy  fibres  ter- 
minate in  a  tendon  which  passes  through  a  groove  in 
the  outer  edge  of  the  lower  extremity  of  the  radius: 

Inserted,  generally  by  two  tendons,  into  the  os  tra- 
pezium, and  into  the  upper  and  back  part  of  the  meta- 
carpal  bone  of  the  thumb. 

Use:  To  extend  the  metacarpal  bone  of  the  thumb 
outwardly. 

8.  The  EXTENSOR  PRIMI  INTERNODII  POLLICIS 
MANUS — Arises^  fleshy,  from  the  back  part  of  the 
ulna  below  its  middle,  from  the  interosseous  ligament 
and  radius.     It  runs  along  the  lower  edge  of  the  ex- 
tensor ossis  metacarpi,  and  forms  a  tendon,  which 
passes  through  the  same  groove  as  the  tendon  of  that 
muscle,  and  is 

Inserted  into  the  posterior  part  of  the  first  bone  of 
the  thumb.  Part  of  the  tendon  is  also  continued  into 
the  base  of  the  second  or  extreme  phalanx. 

Use:  To  extend  the  first  phalanx  of  the  thumb 
obliquely  outwards. 

It  is  called  also  Extensor  secundi  internodii. 

9.  The  EXTENSOR   SECUNDI  INTERNODII'  POLLI- 
CIS MANUS — Arises^  tendinous  and  fleshy,  from  the 
posterior  surface  of  the  ulna  above  its  middle,  and 
from  the   interosseous   ligament.      Its  belly  partly 
covers  the  origins  of  the  two  other  extensors  of  the 
thumb,  and  terminates  in  a  tendon,  which  runs  through 
a  distinct  groove  in  the  back  part  of  the  radius,  and  is 

Inserted  into  the  posterior  and  upper  part  of  the 
second  or  extreme  phalanx  of  the  thumb. 

Use:  To  extend  the  last  joint  of  the  thumb  obliquely 
backwards. 

It  is  called  also  Extensor  tertii  internodii. 

10.  The  INDICATOR,  or  Extensor  Primi  Digit! — 
Jlrises,  by  an  acute  fleshy  beginning,  from  the  middle 

16 


182  LONDON    DISSECTOR,  OR 

of  the  back  part  of  the  ulna,  and  from  the  interosseous 
ligament.  Its  tendon  passes  through  the  same  sheath 
of  the  annular  ligament  with  the  extensor  digitorum 
communis,  and  is 

Inserted  into  the  posterior  part  of  the  fore  finger 
with  the  tendon  of  the  common  extensor. 

Use:  To  assist  in  extending  the  fore  finger. 


SECTI  ON    III. 
DISSECTION    OF   THE    PALM    OF   THE     HAND. 

THE  tendons  which  pass  over  the  bones  of  the  car- 
pus into  the  palm  of  the  hand  are  firmly  bound  down 
by  the  annular  ligament  of  the  wrist.  They  are  in- 
vested and  connected  by  cellular  membrane,  which 
forms  sheaths,  and  secretes  synovia  to  facilitate  their 
motions. 

In  the  sole  of  the  foot  we  saw  a  strong  fascia  sup- 
porting and  covering  the  muscles,  and  passing  from 
the  heel  to  the  toes.  On  removing  the  integuments 
from  the  palm  of  the  hand,  we  meet  with  a  similar 
fascia.  It  arises  from  the  tendon  of  the  palmaris  longus, 
and  from  the  annular  ligament  of  the  wrist,  expands 
over  all  the  palm  of  the  hand,  and  is  fixed  to  the  roots 
of  the  fingers,  splitting,  to  transmit  their  tendons.  This 
is  the  Fascia  or  Aponeurosis  Palmaris.  It  is  triangular. 
Where  it  arises  from  the  wrist,  it  is  narrow,  and  does 
not  cover  the  bases  of  the  metacarpal  bones  of  the  little 
and  fore-finger.  As  it  runs  over  the  hand,  it  becomes 
broader,  and  is  fixed  by  a  bifurcated  extremity  in  the 
lower  end  of  each  of  the  metacarpal  bones  of  the  four 
fingers.  The  palmar  fascia  is  strong  and  thick,  con- 


GUIDE    TO    ANATOMY.  183 

ceals  and  supports  the  muscles  of  the  hand,  and  may 
be  distinguished  into  four  portions,  which  are  con- 
nected by  transverse  fibres,  while  other  fibres  pass 
from  them  downwards,  adhere  strongly  to  the  edges 
of  the  metacarpal  bones,  and  separate  the  tendons  of 
each  finger. 

There  is  a  small  thin  cutaneous  muscle  situated, 
between  the  wrist  and  the  little  finger. 

The  PALMARIS  BREVIS — Arises  from  the  annular 
ligament  of  the  wrist,  and  from  the  inner  edge  of  the 
fascia  palmaris. 

Inserted,  by  small  scattered  fibres,  into  the  skin  and 
fat  which  covers  the  short  muscles  of  the  little  finger 
and  inner  edge  of  the  hand. 

Use:  To  assist  in  contracting  the  palm  of  the  hand. 

The  fascia  palmaris  may  now  be  removed.  Under 
it  will  be  seen  the  four  tendons  of  the  flexor  sublimis 
perforatus.  They  are  seen  coming  from  beneath  the 
annular  ligament  of  the  wrist,  and  diverging  as  they 
pass  towards  their  respective  fingers.  Each  tendon 
splits  at  the  extremity  of  the  first  phalanx,  for  the_ 
passage  of  the  tendon  of  the  flexor  profundus  perfo- 
ratus, and  is  inserted  into  the  base  of  the  second 
phalanx. 

Under  the  flexor  sublimis  are  the  four  tendons  of  the 
flexor  profundus  perforans,which  pass  through  the  slits 
in  the  tendons  of  the  former,  and  are  inserted  into  the 
bases  of  the  third  phalanges  of  the  fingers. 

The  LUMBRICALES  are  four  small  muscles,  which 
«me,  from  the  outer  side  of  the  tendons  of  the  flexor 
profundus  perforans.  The  tendon  of  each  muscle 
runs  along  the  outer  edge  of  the  finger,  and  is 

Inserted  into  the  tendinous  expansion  which  covers 
the  back  part  of  the  phalanges  of  the  fingers,  about 
the  middle  of  the  first  joint. 

Use:  To  bend  the  first  phalanges  of  the  fingers,  the 


184  LONDON    DISSECTOR,  OR 

flexor  profundus  being  previously  in  action,  to  afford 
them  a  fixed  point. 

The  short  muscles  of  the  thumb  and  fore-finger  are 
five  in  number. 

1.  The  ABDUCTOR  POLLICIS  MANUS — Arises,  from 
the  anterior  surface  of  the  annular  ligament  of  the  wrist, 
and  the  os  naviculare  and  os  trapezium. 

Inserted,  into  the  root  of  the  second  bone  of  the 
thumb,  and  the  tendinous  membrane  covering  the  back 
part  of  all  the  phalanges. 

This  muscle  is  situated  immediately  under  the 
integuments,  and  is  the  outermost  portion  of  the  mus- 
cular mass  forming  the  ball  of  the  thumb. 

Use:  To  draw  the  thumb  from  the  fingers. 

2.  The  FLEXOR  Ossis  METACARPI  POLLICIS,  or 
Opponens  Pollicis — Arises,  under  the  last,  from  the 
annular  ligament  of  the  wrist,  and  the  os  naviculare 
and  os  trapezium. 

Inserted,  into  the  anterior  and  lower  part  of  the 
metacarpal  bone  of  the  thumb. 

Use:  To  bring  the  first  bone  of  the  thumb  inwards. 

3.  The  FLEXOR  BREVIS  POLLICIS  MANUS  arises  by 
two  distinct  heads,  (formed  by  the  tendon  of  the  long- 
flexor,)  from  the  inside  of  the  annular  ligament;  from 
the  anterior  surface  of  the  os  trapezium  and  os  trape- 
zoides;  from  the  root  of  the  metacarpal  bone  of  the 
fore  finger;  and  from  the  upper  part  of  the  os  magnum 
and  os  unciforme. 

Inserted  into  the  sesamoid  bones,  and  the  first  pha- 
lanx of  the  thumb. 

This  muscle  is  in  great  part  concealed  by  the 
abductor  pollicis, 

Use:  To  bend  the  first  joint  of  the  thumb. 

4.  The    ADDUCTOR    POLLICIS    MANUS — Arises, 
fleshy,  from  almost  the  whole  length  of  the  metacar- 
pal bone  of  the  middle  finger. 


GUIDE    TO    ANATOMY.  185 

Inserted,  into  the  first  phalanx  of  the  thumb,  at  its 
carpal  extremity. 

Use:  To  pull  the  thumb  towards  the  fingers. 

5.  The  ABDUCTOR  INDICIS  MANUS — Jlrises,  from 
the  os  trapezium,  and  the  metacarpal  bone  of  the 
thumb,  and  is 

Inserted,  into  the  first  phalanx  of  the  fore  finger. 

This  muscle  is  seen  most  distinctly  on  the  back  of 
the  hand.  It  is  there  superficial,  and  is  crossed  by 
the  tendon  of  the  extensor  secundi  internodii  pollicis. 
In  the  palm  of  the  hand  it  is  concealed  by  the  muscles 
of  the  ball  of  the  thumb. 

Use:  To  move  the  fore  finger  towards  the  thumb, 
or  the  thumb  towards  the  fore  finger. 

The  insertion  of  the  flexor  carpi  radialis  is  exposed 
by  removing  the  muscles  of  the  thumb. 

The  short  muscles  of  the  little  finger  are  three  in 
number. 

1.  The    ABDUCTOR    MINIMI    DIGITI  MANUS — 
Jlrises,  from  the  os  pisiforme,  and  adjacent  part  of  the 
annular  ligament  of  the  wrist. 

Inserted,  into  the  side  of  the  first  phalanx,  and  the 
tendinous  expansion  which  covers  the  back  part  of 
the  little  finger. 

Use:  To  draw  the  little  finger  from  the  rest. 

2.  The  FLEXOR  PARVUS  MINIMI  DIGITI — Arises, 
fleshy,  from  the  outer  side  of  the  os  unciforme,  and 
from  the  annular  ligament  of  the  wrist,  where  it  is 
affixed  to  that  bone. 

Inserted,  by  a  roundish  tendon,  into  the  base  of  the 
first  phalanx  of  the  little  finger. 

Use:  To  bend  the  little  finger,  and  bring  it  towards 
the  other  fingers. 

3.  ADDUCTOR  METACARPI  MINIMI  DIGITI  MANCS, 
Arises,  from  the  os  unciforme,  and  adjacent  part  of  the 
annular  ligament  of  the  wrist. 

16* 


18&  LONDON    DISSECTOR,    OR 

Inserted,  into  the  fore  part  of  the  metacarpal  bone 
of  the  little  finger,  nearly  its  whole  length. 

It  is  concealed  by  the  bellies  of  the  abductor  and 
flexor  brevis  minimi  digiti. 

Use:  To  bend  and  bring  the  metacarpal  bone  of  the 
little  finger  towards  the  rest. 

The  INTEROSSEI  are  small  muscles  situated  between 
the  metacarpal  bones,  and  extending  from  the  bones 
of  the  carpus  to  the  fingers.  They  are  exposed  by 
removing  the  other  muscles  of  the  thumb  and  fingers. 

The  INTEROSSEI  INTERNI  are  seen  in  the  palm  of 
the  hand,  and  are  four  in  number.  They  arise,  tendi- 
nous and  fleshy,  from  the  base  and  sides  of  the  meta- 
carpal bones,  and  are  inserted  into  the  side  of  the  first 
phalanx  of  the  fingers,  and  into  the  tendinous  expansion 
which  covers  the  posterior  surface  of  all  the  phalanges. 

1.  The  First,  named  Prior  Indicis,  arises  from  the 
outer  part  of  the  metacarpal  bone  of  the  fore-finger; 
and  is  inserted  into  the  outer  side  of  the  first  phalanx 
of  that  finger. 

Use:  To  draw  the  fore-finger  towards  the  thumb. 

2.  The   Second,  named  Posterior  Indicis,  arises 
from  the  root  and  inner  side  of  the  metacarpal  bone 
of  the  fore-finger;  and  is  inserted  into  the  inner  side  of 
the  first  phalanx  of  the  fore-finger. 

Use:  To  draw  that  finger  outwards. 

3.  The  Third,  named  Prior  Annularis,  arises  from 
the  root  and  outer  side  of  the  metacarpal  bone  of  the 
ring-finger;  and  is  inserted  into  the  outer  side  of  the 
first  phalanx  of  the  same  finger. 

Use:  To  pull  the  ring-finger  towards  the  thumb. 

4.  The*  Fourth,   named  Interosseus   Auricularis, 
arises  from  the  root  and  outer  side  of  the  metacarpal 
bone  of  the  little  finger;  and  is  inserted  into  the  outer 
side  of  the  first  phalanx  of  the  little  finger. 

Use:  To  draw  the  little  finger  outwards. 


GUIDE    TO    ANATOMY.  187 

The  internal  interossei  also  assist  in  extending  the 
fingers  obliquely. 

The  INTEROSSEI  EXTERNI,  seu  Bicipites,  are  three 
in  number.  They  are  larger  than  the  internal,  and 
are  situated  between  the  metacarpal  bones  on  the  back 
of  the  hand.  Each  of  these  muscles  arises  by  a  double 
head,  from  two  metacarpal  bones,  and  is  inserted  into 
the  side  of  one  of  the  fingers,  and  into  the  tendi- 
nous expansion  which  covers  the  posterior  part  of 
the  phalanges. 

1 .  The  First,  named  Prior  Medii,  arises  from  the 
roots  of  the  metacarpal  bones  of  the  fore  and  middle 
fingers;  and  is  inserted  into  the  outer  side  of  the  mid- 
dle finger. 

Use:  To  draw  the  middle  finger  towards  the  thumb. 

2.  The  Second,  named  Posterior  Medii,  arises  from 
the  roots  of  the  metacarpal  bones  of  the  middle  and 
ring  fingers;  and  is  inserted  into  the  inner  side  of  the 
middle  finger. 

Use:  To  draw  the  middle  finger  towards  the  ring- 
finger. 

3.  The  Third,  named  Posterior  Annularis,  arises 
from  the  roots  of  the  metacarpal  bones  of  the  ring  and 
little  fingers;  and  is  inserted  into  the  inner  side  of  the 
ring-finger. 

Use:  To  draw  the  ring-finger  inwards.  The  ex- 
ternal  interossei  also  extend  the  fingers. 


PART   II. 


DISSECTION    OF    THE    VASCULAR 
AND    NERVOUS    SYSTEMS. 


WE  will  suppose  that  the  subject  has  been  injected; 
and  that  the  student  proceeds  to  the  examination  of  the 
lower  extremity.  He  may  proceed  according  to  the 
rules  laid  down  for  the  dissection  of  the  abdominal 
muscles,  and  having  carefully  raised  the  external  ob- 
lique he  will  meet  in  the  region  of  the  abdominal  ring 
the  epigastric  artery,  and  the  circumflexa  ilii,  branches 
of  the  external  iliac  artery. 

The  Epigastric  Jlrtery  comes  off  from  the  inside  of 
the  external  iliac,  crosses  the  external  iliac  vein^ 
passes  obliquely  upwards  and  inwards,  under  Pou- 
part's  ligament,  to  which  it  is  but  loosely  connected, 
and  runs  behind  the  upper  extremity  of  the  abdomi- 
nal ring  and  spermatic  chord,  to  reach  the  rectus  ab- 
dominis.  At  first  it  is  situated  between  the  posterior 
surface  of  that  muscle  and  the  peritoneum,  but  higher 
up  between  the  muscular  fibres  and  the  sheath.  It 
terminates  in  ramifications,  which  supply  the  rectus, 
and  which  inosculate  with  those  of  the  mammaria 
interna,  sent  down  from  the  thorax  on  each  side  of  the 
sternum. 

The  circumflexa  Ilii  is  sent  off  from  the  outside  of 
the  external  iliac,  passes  upwards  and  outwards,  runs 
along  the  inside  of  Poupart's  ligament,  till  it  arrives 
at  the  anterior  superior  spinous  process  of  the  os 
ilium;  thence  it  is  continued  along  the  inside  of  the 


190  LONDON    DISSECTOR,  OR 

spine  of  the  ilium,  lying  close  upon  the  bone  between 
the  transversalis  abdominis  and  the  upper  edge  of  the 
iliacus  internus,  to  both  of  which  it  gives  twigs,  and 
ends  in  inosculating  with  the  ileo-lumbar  artery.  The 
muscles  of  the  abdomen  may  now  be  removed;  and 
having  cut  through  the  peritoneum,  the  student  will 
meet  with  the  abdominal  aorta  and  its  various  branches. 


OF  THE  VESSELS  AND  NERVES  SITUATED 
BEHIND  THE  PERITONEUM. 

1 .    THE    ARTERIES,    viz:     THE     AORTA     ABDOMIN  ALIS, 
AND    ITS    BRANCHES. 

THE  Aorta  passes  from  the  thorax  into  the  abdo- 
men, between  the  crura  of  the  diaphragm,  close  upon 
the  spine.  It  then  descends  on  the  fore  part  of  the 
vertebrae,  lying  not  exactly  in  the  middle,  but' rather 
inclined  to  the  left  side.  On  the  fourth  lumbar^  ver- 
tebra, it  bifurcates  into  the  two  primitive  or  common 
iliac  arteries. 

'BRANCHES  OF  THE  ABDOMINAL  AORTA. 

1.  The  two  PHRENIC  Arteries  arise  from  the  Aorta, 
before  it  has  fairly  entered  into  the  abdomen,  and 
ramify  over  the  diaphragm; — sometimes  they  come  off 
in  one  trunk,  which  bifurcates;   sometimes  one   of 
them  arises  from  the  coeliac. 

2.  The  COELIAC  Artery  comes  off  at  the  point  where 
the  aorta  has  fairly  extricated  itself  from  the  dia- 
phragm; it  is  a  single,  large,  But  short  trunk,  situated 
between  the  inferior  surface  of  the  liver,  and  the  small 
curvature  of  the   stomach,  and   surrounded  by  the 
meshes  of  the  semilunar  ganglion.     It  divides  at  once 


GUIDE    TO    ANATOMY.  191 

into  three  branches;  and  as  they  depart  in  different 
directions  from  one  point,  as  from  a  centre,  the  trunk 
is  called  the  Axis  ARTERIES  CCELIAC^E. 

(1.)  A.  CORONARIA  VENTRICULI,  the  middle  branch, 
is  the  smallest  of  the  three;  it  pas&es  from  the  axis 
towards  the  left  side,  and  arriving  at:  the  cardiac 
orifice  of  the  stomach,  where  it  attaches  itself  to  that 
organ,  sends  a  branch  round  the  cardia,  named  Ramus 
Coronarice  Dexter.  The  trunk  itself  is  then  continued 
along  the  lesser  curvature  from  left  to  right,  to  inos- 
culate with  the  pylorica  or  coronaria  dextra:  it  sends 
off  branches  to  the  little  epiploon,  &c.  It  sometimes 
terminates  in  the  liver,  entering  at  the  portae,  and 
then  it  is  the  largest  of  the  branches  of  the  coeliac. 
In  this  case,  the  trunk,  after  ascending  towards  the 
left  to  reach  the  cardia,  is  reflected  to  the  right,  in 
its  way  to  the  liver;  and,  at  the  point  of  reflection, 
gives  off  the  coron.  ventric. 

(2.)  ARTERIA  SPLENICA,  leaving  the  trunk  of  the 
coeliac,  goes  directly  to  the  side,  passes  under  the 
stomach,  and  along  the  upper  border  of  the  pancreas, 
running  in  a  tortuous  and  serpentine  course:  it  enters 
the  left  concave  surface  of  the  spleen  in  several 
branches,  but  before  doing  so,  it  gives  off  the  follow- 
ing branches: 

#,  PANCREATICE  PARVJE  to  the  pancreas,  where 
it  runs  along  the  border  of  that  viscus. 

6,  VASA  BREVIA  to  the  bulging  extremity  of  the 
stomach. 

c,  A.  GASTRO-EPIPLOICA  SINISTRA,  which  runs 
along  the  greater  curvature  of  the  stomach,  inosculat- 
ing with  the  gastro-epiploica  dextra. 

(3.)  ARTERIA  HEPATICA  runs  in  a  direction  oppo- 
site to  the  splenic,  towards  the  right  side;  but  not  more 
than  half  of  its  blood  goes  to  the  liver:  It  sends  off 
the  following  branches: 

#,  PYLORICA,  or  CORONARIA  DEXTRA,  sometimes 


192  LONDON    DISSECTOR,  OR 

comes  off  from  the  trunk  of  the  hepatic,  sometimes 
from  one  of  its  branches: — reaching  the  pyloric  end 
of  the  stomach,  it  sends  its  ramifications  along  the 
lesser  curvature,  to  inosculate  with  the  proper  coro- 
nary artery.' 

6,  GASTRO-EPIPLOICA  DEXTRA,  or  GASTRO-DUO- 
DENALIS,  passes  under  the  pylorus,  to  reach  the  great 
curvature  of  the  stomach,  along  which  it  runs,  inoscu- 
lating with  the  gastro-epiploica  sinistra,  and  sending 
branches  upwards  to  the  stomach,  and  downwards  to 
the  omentum;  it  also  supplies  the  upper  part  of  the 
duodenum,  and  sends  off  a  considerable  branch  to  the 
right  extremity  of  the  pancreas. 

The  hepatic  artery  then  divides  into  the  right  and 
left  hepatic.  The  RIGHT  is  distributed  to  the  right 
lobe  of  the  liver,  and  to  the  gall-bladder.  The  LEFT 
supplies  the  whole  of  the  left  lobe,  the  lobulus  Spigelii, 
and  part  of  the  right  lobe  of  the  liver. 

3.  The  SUPERIOR  MESENTERIC  ARTERY  is  a  single 
trunk;  it  leaves  the  aorta  about  half  an  inch  lower  than 
the  coeliac  artery,  it  comes  out  from  under  the  mesoco- 
lon,  and  stretches  over  the  duodenum:  it  enters  the  fold 
of  peritoneum  forming  the  mesentery,  and  runs  down 
in  this,  gradually  incurvating  from  the  left  to  the  right 
side. 

From  the  right  side  or  concavity  of  this  arch,  three 
branches  are  given  to  the  colon. 

(1.)  A.  ILEO-COLICA  runs  down  to  the  caput  coli 
and  last  turns  of  the  ileon;  its  branches  upon  the 
small  intestines  inosculate  with  those  branches  of  the 
superior  mesenteric  distributed  to  the  small  intestines 
in  general;  and  on  the  great  intestine,  it  inosculates 
with  the  next  branch. 

(2.)  A.  COLICA  DEXTRA. — This  artery  runs  from 
the  root  of  the  superior  mesenteric  artery,  across 
towards  the  right  side  of  the  colon,  where  that  intes- 
tine begins  to  rise  over  the  kidney-. 


GUIDE    TO    ANATOMY.  193 

(3.)  A.  COLICA  MEDIA. — This  branch  goes  directly 
upwards  from  the  trunk  of  the  superior  mesenteric, 
as  it  comes  out  from  under  the  mesocolon.  After 
running  a  little  way  upon  the  mesocolon,  it  divides; 
and  the  division  going  towards  the  right  side,  makes 
a  large  inosculation  with  the  colica  dextra,  while  the 
left  branch  makes  an  opposite  sweep,  and  joins  the 
colica  sinistra,  which  is  a  branch  of  the  inferior 
mesenteric. 

Often  there  are  only  two  branches  instead  of  these 
three;  viz.  ileo-colica^  and  colica  dextra;  then  the  c. 
media  is  a  branch  of  the  latter.  Frequently  too,  there 
is  only  one  branch,  called  colica  dextra^  and  dividing 
after  its  origin,  into  the  three  above  named. 

The  left  side  or  convexity  of  the  arch  of  the  supe- 
rior mesenteric  sends  off  from  sixteen  to  twenty 
branches,  which,  after  forming  frequent  anastomoses 
and  arches,  proceed  to  the  small  intestines. 

4.  The  RENAL  or  EMULGENT  ARTERIES  are  two 
in  number.     Each  artery  arising,  below  the  superior 
mesenteric,  from  the  side  of  the  aorta,  passes  to  the 
kidney,  and  after  having  given  twigs  to  the  renal  cap- 
sule, and  adipose  membrane,  enters  the  smaller  arch 
of  the  kidney.     The  right  artery  is  longer  than  the 
left,  and  passes  behind  the  vena  cava  ascendens. 

5.  The  SPERMATIC  ARTERIES  are  also  two;  they 
come  off  about  an  inch  below  the  emulgent  from  the 
fore  part  of  the  aorta.     Each  artery  descends  behind 
.the  peritoneum,  giving  twigs  to  the  parts  in  its  course, 
and  accompanied  by  the  spermatic  vein  and  nerves. 
It  then  passes  through  the  abdominal  ring,  and  enters 
the  upper  part  of  the  testicle  in  five  or  six  branches. 
In  the  female  it  supplies  the  ovaria  and  fundus  uteri. 

6.  The  INFERIOR  MESENTERIC  is  a  single  trunk, 
which  comes  off  rather  from  the  left  side  of  the  aorta, 
below  the  spermatic  arteries;  it  passes  in  the  mesentery 

17 


194  LONDON    DISSECTOR,  OR 

to  the  left  side  of  the  abdomen,  where  it  divides  as 
follows: 

(1.)  The  COLICA  SINISTRA,  an  artery  which  ascends 
along  the  left  side  of  the  colon,  to  inosculate  with  the 
A.  Colica  Media. 

(2.)  Branches  which  pass  to  the  sigmoid  flexure. 

(3.)  The  great  trunk  of  the  artery  runs  down  behind 
the  rectum,  on  which  it  ramifies  largely,  and  is  termed 
ART.  HEMORRHOIDALIS  INTERNA. 

7.  The  LUMBAR  ARTERIES  are  five  or  six  small 
arteries  on  each  side,  which  arise  from  the  back  part 
of  the  aorta,  and  are  distributed  to  the  spinal  canal, 
peritoneum,  muscles  of  the  spine,  and  of  the  sides  of 
the  abdomen  and  pelvis.   They  inosculate  with  the  A. 
Epigastrica,  Circumflexa  ilii  &c. 

8.  A.  SACRA  MEDIA  is  a  single  artery,  arises  from 
the  back  part  of  the  aorta  at  its  bifurcation,  and 
descends  along  the  anterior  surface  of  the  sacrum, 
giving  twigs  to  all  the  neighboring  parts. 

At  the  fourth  lumbar  vertebra,  the  aorta  bifurcates 
into  the  two  primitive  or  common  iliacs. 

The  ILIACA  COMMUNIS  runs  along  the  edge  of  the 
psoas  muscle,  and  at  an  inch  or  two  from  its  origin 
divides  into, 

(1.)  The  Internal  Iliac,  which  passes  down  into  the 
pelvis. 

(2.)  The  External  Iliac,  which,  following  the  direc- 
tion of  the  psoas  muscle,  passes  under  Poupart's  liga- 
ment, and  becomes  the  inguinal  artery. 

2.   VEINS. 

The  VENA  CAVA  ABDOMINALIS,  vel  Inferior,  is 
formed  by  the  junction  of  the  two  common  iliac  veins; 
it  passes  up  through  the  abdomen  on  the  lumbar  ver- 
tebra, and  on  the  right  side  of  the  aorta. 


GUIDE    TO    ANATOMY.  195 

In  this  course  it  receives  the  following  veins,  which 
resemble  their  corresponding  arteries. 

1 .  The  Lumbar  Veins. 

2.  The  Emulgent  or  Renal  Veins;— the  left  is  the 
longer,  as  it  crosses  over  the  fore  part  of  the  aorta. 

3.  The  Right  Spermatic  Vein; — the  left  enters  the 
left  renal  vein. 

The  vena  cava  then  passes  through  the  fissure  of 
the  liver,  being  nearly  surrounded  by  that  viscus,  and 
receiving  three  branches  from  it,  called  the  VEN^S 
HEPATIC^:.  It  then  perforates  the  diaphragm,  and 
enters  the  thorax. 

The  common  iliac  vein  of  each  side  is  formed  by  the 
union  of  two  branches,  the  EXTERNAL  and  INTERNAL 
ILIAC  VEINS,  which  accompany  the  arteries  of  the 
same  name: — The  common  iliac  vein  of  each  side  lies 
on  the  inside  of  its  artery;  hence  both  veins  cross  be- 
hind the  right  iliac  artery,  to  unite  and  form  the  vena 
cava,  on  the  fore  part  of  the  lumbar  vertebras.* 

'do  not  join  the  cava,  but 


The  SUPERIOR  MES- 
ENTERIC  VEIN,  the  IN- 
FERIOR MESENTERIC 
VEIN,  and  the  SPLENIC 
VEIN, 


are  united  behind  the 
pancreas,  to  form  the 
Vena  Portae.  This  vein 
ramifies  anew  through 
the  liver,  and  its  blood 
is  returned  into  the  vena 


cava   by  the  venae  cavae 
[  hepaticae. 

Although  the  trunks  just  enumerated  are  the  chief 
veins  that  contribute  to  form  the  vena  portae,  yet  the 
returning  veins  of  all  the  viscera  enclosed  in  the  peri- 
toneum, except  the  liver,  are  included  in  the  same 
system,  and  join  one  or  other  of  the  large  trunks.  This 
is  the  case  with  the  stomach,  pancreas,  gall-bladder, 

*  It  may  be  here  proper  to  observe,  that  generally  a  great  vein  accom- 
panies every  great  artery;  but  when  the  ramifications  become  small, 
each  artery  is  attended  by  two  veins. 


196  LONDON    DISSECTOR,  OR 

and  omentum.  The  blood  which  goes  to  the  spleen, 
large  and  small  intestines,  is  all  returned  by  the  three 
great  trunks. 

3.    NERVES. 

1 .  The  eighth  pair,  or  Par  Vagum,  descending  on 
each  side  of  the  oesophagus  through  the  diaphragm, 
forms  'the  two  STOMACHIC  PLEXUSES  on  the  anterior 
and  posterior  surfaces  of  the  stomach.   These  plexuses 
send  some  branches  to  the  coeliac,  to  the  hepatic,  and 
to  the  splenic  plexus. 

2.  The  SPLANCHNIC  NERVE,  or  Anterior  Intercos- 
tal, a  branch  sent  off  by  the  intercostal  nerve  in  the 
thorax,  enters  the  abdomen  betwixt  the  crura  of  the 
diaphragm;  here  each  nerve  forms   a   SEMILUNAR 
GANGLION  by  the  side  of  the  coeliac  artery. 

From  this  ganglion,  on  each  side,  branches  are  sent 
across,  which  communicate  intimately  together,  and 
form  round  the  root  of  the  coeliac  artery,  a  very  inti- 
mate plexus,  containing  several  ganglia  of  various 
sizes,  formerly  called  the  SOLAR,  but  now  more  cor- 
rectly the  CCELIAC  PLEXUS.  Nerves  pass  from  this 
plexus,  with  the  branches  of  the  aorta,  to  the  various 
viscera  of  the  abdomen:  in  a  common  dissection  these 
nerves  cannot  be  clearly  demonstrated,  as  they  lie  very 
close  on  the  respective  arteries,  and  are  surrounded 
by  much  condensed  cellular  substance;  they  form  the 
hepatic,  splenic,  superior,  and  inferior  mesenteric, 
renal,  and  spermatic  plexuses. 

3.  The  trunk  of  the  intercostal  nerve,  the  posterior 
intercostal,  perforates  the  small   muscle  of  the  dia- 
phragm close  to  the  spine,  runs  down  on  the  sides  of 
the  lumbar  vertebrae,  and  along  the  upper  edge  of  the 
psoas  magnus.     It  terminates  on  the  extremity  of  the 
os  coccygis,  by  union  with  the  nerve  of  the  opposite 
side,  in  a  ganglion  named  GANGLION  IMPAR.     In  this 


GUIDE    TO    ANATOMY.  197 

course,  it  communicates  with  the  lumbar  nerves,  and 
the  various  abdominal  plexuses. 

The  THORACIC  DUCT  may  be  seen  passing  from 
the  abdomen  into  the  thorax,  between  the  aorta  and 
the  right  crus  of  the  diaphragm.  It  is  larger  here 
than  in  its  subsequent  course,  and  the  dilated  portion 
is  called  receptaculum  chyli,  as  the  lacteals  pour  in  the 
chyle  in  this  situation. 


OF  THE  VESSELS  AND  NERVES  CONTAINED 
A.  WITHIN  THE  PELVIS. 

1.    ARTERIES. 

THE  A.  ILIACA  INTERNA,  having  left  the  trunk  of 
the  iliaca  communis,  passes  immediately  into  the  pel- 
vis, where  it  gives  off  several  large  arteries. 

1 .  A.  ILEO-LUMBALIS  supplies  the  psoas  and  iliacus 
internus  muscles. 

2.  A.  SACR^E  LATERALES,  two  or  three  small  ves- 
sels which   supply  the  sacrum,  cauda  equina,  and 
neighboring  parts. 

3.  A.  GLUTEA  (or  iliaca  posterior,)  a  very  large 
branch,  passes  out  of  the  pelvis  through  the  upper 
part  of  the  sciatic  notch  to  supply  the  haunch,  but,  in 
its  passage,  it  gives  some  branches  to  the  os  sacrum, 
os  coccygis,  the  rectum,  and  the  muscles   situated 
within  the  pelvis. 

4.  A.  SCIATICA  passes  out  of  the  pelvis  by   the 
sciatic  notch,  and  below  the  pyriformis  muscle   to 
supply  the  hip:  in  its  passage  it  gives  branches  to  the 
neighboring  parts. 

5.  A.  PUDICA  (pudenda  communis  or  interna)  is  the 
branch  of  the  internal  iliac,  which  is  more  immediately 
destined  to  supply  the  parts  of  generation,  perineum, 
and  lower  part  of  the  rectum:  it  goes  out  of  the  pelvis 

17* 


198  LONDON    DISSECTOR,  OR 

above  the  superior  sacro-sciatic  ligament,  twists  round 
it,  and  re-enters  the  pelvis  above  and  before  the  infe- 
rior sacro-sciatic  ligament;  it  then  descends  on  the 
inside  of  the  tuber  ischii,  ascends  on  the  inner  surface 
of  the  rami  of  the  ischium  and  pubis,  and,  reaching 
the  root  of  the  penis,  divides  into  two  branches. 

(1.)  A.  PERINEI,  a  branch  which,  after  giving 
twigs  to  the  bulb  of  the  urethra  and  neighboring 
muscles,  enters  the  crus  of  the  penis,  and  subdivides 
into  branches  which  pass  to  both  extremities  of  the 
crus. 

(2.)  A.  DORSALIS  PENIS,  passes  under  the  arch  of 
the  pubis,  runs  along  the  dorsum  penis,  and  is  distri- 
buted to  the  integuments. 

In  its  course  the  pudic  artery  gives  off  many 
branches. 

(1.)  While  in  the  pelvis,  it  gives  twigs  to  the  blad- 
der, prostate  gland,  and  rectum. 

(2.)  A.    H^MORRHOIDALES    EXTERN^    COme    frOfi^ 

the  pudic  while  passing  by  the  anus. 

(3.)  A.  TRANSVERSA  PERINEI,  following  the  course 
of  the  transversus  perinei  muscle. 

(6.)  A.  OBTURATRIX  descends  on  the  inside  of  the 
psoas  muscle,  passes  through  the  foramen  in  the  ob- 
turator ligament  to  the  muscles  on  the  inside  of  the 
thigh. 

(7.)  A.  HYPOGASTRICA,  which  in  the  foetus  sends 
off  the  umbilical  artery,  is  in  the  adult  continued  only 
to  the  side  of  the  bladder,  to  which  it  gives  branches; 
in  the  female,  it  enters  the  neck  of  the  uterus,  and 
gives  branches  to  the  vagina. 

You  must  not  expect  to  meet  with  uniformity  in  the 
distribution  of  these  vessels  in  all  subjects:  sometimes 
the  gluteal  and  pudic  arteries  come  off  by  one  trunk, 
sometimes  the  pudic  and  sciatic,  &c.  &c. 


GUIDE    TO    ANATOMY.  199 

2.    VEINS. 

The  veins  attend  the  arteries  and  their  ramifications; 
they  unite  to  form  the  internal  iliac  vein,  except  the 
veins  from  the  rectum,  named  HcemorrhoidaleSj  which 
ascend  along  its  back  part  to  join  the  inferior  mesen- 
teric  vein. 

3.  NERVES. 

The  nerves  met  with  in  this  dissection,  consist  of 
numerous  twigs  sent  off  from  the  lumbar  and  sacral 
nerves  to  supply  the  parts  about  the  pelvis. 

But,  in  this  dissection,  we  meet  with  three  pair  of 
large  nerves,  which  have  their  course  through  the 
pelvis,  and  pass  to  the  thigh. 

1 .  Course  of  the  ANTERIOR  CRURAL  NERVE  while 
in  the  pelvis.     The  anterior  crural  nerve  is  formed 
by  branches  of  the  first,  second,  third,  and  fourth 
lumbar  nerves;  at  its  origin,  it  lies  under  the  psoas 
magnus,  and,  as  it  descends,  passes  betwixt  the  psoas 
magnus  and  iliacus  internus,  till  having  passed  under 
Poupart's  ligament,  it  emerges  from  betwixt  those 
muscles,  and  appears  on  the  outer  side  of  the  inguinal 
artery. 

2.  Course  of  the  OBTURATOR  NERVE  within  the 
pelvis.     This  nerve  is  formed  by  branches  of  the 
second,  third,  and  fourth  lumbar  nerves:  it  lies  under 
the  internal  border  of  the  psoas  magnus,   descends 
into  the  pelvis,  and  goes  obliquely  downwards,  to 
accompany  the  obturator  artery  through  the  thyroid 
hole. 

3.  Course  of  the  GREAT  SCIATIC  NERVE  within 
the  pelvis.     This  nerve  arises  by  branches  from  the 
fourth  and  fifth  lumbar,  and  first  three  sacral  nerves, 
which  unite  together  to  form  the   largest  nervous 
trunk  in  the  body.     The  nerve  passes  betwixt  the 
pyriformis   and  gemini,  and  thus  escapes  from  the 


200  LONDON    DISSECTOR,  OR 

back  part  of  the  pelvis  by  the  sciatic  notch.  Some- 
times one  of  the  branches  goes  through  the  pyriformis, 
and  joins  the  sciatic  trunk  at  the  back  of  the  pelvis. 


ARTERIES,  VEINS,  AND  NERVES  ON 

THE  FORE  PART  AND  INSIDE 

OF  THE  THIGH. 

1.    ARTERIES. 

THE  FEMORAL  ARTERY  may  be  said  to  pass  along 
the  inside  of  the  thigh,  where  it  emerges  from  under 
Poupart's  ligament;  it  lies  cushioned  on  the  fibres  of 
the  psoas  magnus,  is  called  the  Inguinal  artery,  and 
is  very  nearly  in  the  mid  space  between  the  angle  of 
the  pubis,  and  the  anterior  superior  spine  of  the  ilium, 
nearer,  however,  by  a  finger's  breadth  to  the  former, 
having  left  the  groin,  it  assumes  the  name  of  Femoral, 
and,  in  its  course  down  the  thigh,  runs  over  the  fol- 
lowing muscles: — The  pectinalis,  part  of  the  adductor 
brevis,  where  that  muscle  projects  betwixt  the  pecti- 
nalis and  adductor  longus;  the  whole  of  the  adductor 
longus,  and  about  an  inch  of  the  adductor  magnus:  It 
then  slips  betwixt  the  tendon  of  the  adductor  magnus 
and  the  bone,  and,  entering  the  ham,  becomes  the 
Popliteal  artery.  To  find  the  artery  in  any  part  of 
its  course  from  the  crural  arch  to  the  tendinous  opening, 
turn  out  the  foot,  ascertain  the  place  of  that  vessel  at 
the  crural  arch,  according  to  the  above  description, 
and  then  draw  a  straight  line  downwards.  In  this 
course,  it  has  the  belly  of  the  vastus  internus  situated 
on  its  outside;  it  lies  between  the  origin  of  that  mus- 
cle, and  the  tendinous  insertion  of  the  muscles  over 
which  it  crosses;  and  there  is  a  strong  interlacing  of 
the  tendinous  fibres,  forming  a  deep  groove  for  the 
artery;  it  is  also  invested  by  a  firm  sheath,  which 


GUIDE   TO    ANATOMY.  201 

consists  of  condensed  cellular  membrane,  intermixed 
with  some  tendinous  fibres: — For  some  inches  below 
Poupart's  ligament,  this  artery  is  on  its  fore  part  only 
covered  by  cellular  substance,  absorbent  glands,  and 
the  general  fascia  of  the  thigh;  but,  meeting  with  the 
inclined  line  of  the  sartorius.  it  is,  during  the  rest  of 
its  course,  covered  by  that  muscle.  It  perforates  the 
tendon  of  the  adductor  magnus,  at  the  distance  of 
rather  more  than  one-third  of  the  length  of  the  bone 
fromjits  lower  extremity. 

Observe  that:  in  popliteal  aneurism  the  artery  may 
be  taken  up  either  at  the  upper  or  inner,  the  lower  or 
outer,  margin  of  the  Sartorius,  or  immediately  behind 
that  muscle:  of  which  situations  the  first  is  the  best, 
the  second  next,  and  the  third  by  far  the  least  eligible. 

BRANCHES     OF     THE     FEMORAL     ARTERY.* 

The  A.  PROFUNDA  comes  off  from  the  femoral 
artery  at  the  distance  of  two,  three  or  four  inches  from 
Poupart's  ligament;  it  is  nearly  as  large  as  the  femoral 
itself,  runs  down  for  some  little  way  behind  it,  and 
terminates  in  three  or  four  branches,  which,  perfora- 
ting the  triceps  adductor,  are  named  ARTERLE  PER- 
FORANTES.  These,  ramifying  in  every  direction, 
supply  all  the  great  mass  of  muscles  situated  on  the 
back  part  of  the  thigh,  and  inosculate  largely  with  the 
sciatic,  gluteal,  and  obturator  arteries.  The  profunda 
also  sends  off  two  considerable  branches,  which,  en- 
circling the  upper  part  of  the  thigh,  are  named  CIR- 
CUMFLEXA  INTERNA,  and  CIRCUMFLEXA  EXTERNA. 

The  profunda  is  the  only  branch  of  the  femoral 
artery  which  is  constant  in  its  size  and  situation;  for 
though,  during  the  whole  of  its  course,  the  femoral 
gives  off  branches  to  the  muscles,  yet  these  muscular 
arteries  vary  much,  sometimes  coming  off  from  the 

*The  Epigastrica  and  Circumflexa  ilii  are  before  described  as  branches 
of  the  inguinal  artery. 


202  LONDON   DISSECTOR,  OR 

great  artery,  sometimes  from  the  profunda,  sometimes 
coming  off  as  a  large  single  trunk  which  subdivides, 
while  at  other  times  there  are  three  or  four  distinct 
arteries. 

The  branches  of  the  femoral  artery  may  be  enume- 
rated as  follows: — 1.  Some  twigs  to  the  inguinal 
glands,  and  some  to  the  external  parts  of  generation, 
named  Pudicae  Externae.  2.  Muscularis  interna. 
3.  Muscularis  externa.  4.  Profunda. 

The  OBTURATOR  ARTERY,  arteria  obturatrix,  which 
is  a  branch  of  the  internal  iliac  artery,  passes  through 
the  notch  at  the  upper  part  of  the  foramen  thyroideum, 
and  ramifies  on  the  deep  seated  muscles  at  the  upper 
and  inner  part  of  the  thigh. 

2.  VEINS. 

The  FEMORAL  VEIN  adheres  closely  to  the  femoral 
artery  in  its  passage  out  of  the  abdomen,  and  accom- 
panies it  in  its  course  down  the  thigh,  where  it  passes 
under  Poupart's  ligament;  it  lies  on  the  inside  of  the 
artery,  but,  as  it  descends,  it  turns  more  and  more 
posteriorly,  so  that  where  they  perforate  the  tendon 
of  the  adductor  magnus,  the  vein  is  situated  fairly 
behind  the  artery. 

Its  branches  correspond  to  those  of  the  femoral  ar- 
tery; but  about  an  inch  below  Poupart's  ligament,  it 
receives  the  vena  saphena  major,  to  which  there  is  no 
corresponding  artery. 

The  OBTURATOR  VEIN  accompanies  the  obturator 
artery,  and  has  the  same  distribution. 

3.    NERVES. 

NERVUS  CRURALIS  ANTERIOR,  or  the  Anterior 
Crural  nerve,  where  it  passes  from  under  Poupart's 
ligament,  lies  about  half  an  inch  on  the  outside  of  the 


GUIDE    TO    ANATOMY.  203 

femoral  artery;  it  immediately  divides  into  a  number 
of  branches,  which  supply  the  muscles  and  integuments 
on  the  fore  part  and  outside  of  the  thigh.  A  consider- 
able branch,  however,  accompanies  the  femoral  ar- 
tery, crosses  that  vessel  where  it  is  about  to  perforate 
the  adductor  magnus,  runs  behind  the  sartorius,  and 
appears  as  a  cutaneous  nerve  on  the  inside  of  the  knee: 
proceeding  downwards  on  the  inside  of  the  leg,  it  is 
largely  distributed  over  the  tibia,  is  intricated  with  the 
vena  saphena  major,  and  terminates  on  the  inner  ankle, 
and  upper  part  of  the  foot.  This  branch  is  named 
NERVUS  SAPHENUS,  or  CUTANEUS  LONGUS. 

Another  branch,  which  is  distributed  to  the  vastus 
internus,  generally  runs  for  some  way  in  company  with 
the  femoral  vessels. 

NERVUS  OBTURATOR,  or  the  obturator  nerve,  is 
found  accompanying  the  obturator  artery  and  vein;  it 
has  the  same  distribution,  and  some  branches  extend 
as  far  as  the  internal  condyle  of  the  thigh  bone,  and 
communicate  with  the  nervus  saphenus. 


VESSELS  AND  NERNES  ON  THE  POS- 
TERIOR  PART  OF  THE  THIGH. 

ARTERIES. 

1.   ARTERIA  GLUTEA,  or  ILIACA  POSTERIOR^ — 

This  is  the  largest  branch  of  the  internal  iliac  artery; 
it  passes  out  of  the  pelvis  at  the  upper  part  of  the 
sciatic  notch.  On  raising  the  gluteus  maximus  and 
medius,  this  artery  is  seen  coming  over  the  pyriformis, 
betwixt  the  superior  edge  of  that  muscle  and  the  infe- 
rior edge  of  the  os  ilium  (where  that  bone  forms  the 
upper  part  of  the  sciatic  notch,)  and  immediately 


204 

behind  the  posterior  fibres  of  the  gluteus  minimus. 
The  principal  trnnV  passes  under  the  gluteus  medius, 
and  ramifies  on  the  dorsum  of  the  os  ilium;  other  large 
branches  are  also  continued  to  the  gluteus  maximus, 
and  the  muscles  situated  on  the  back  part  of  the 
pelvis. 

2.  ARTERIA  SCIATICA,  vel  ISCHIATICA,  is  another 
large  branch  of  the  internal  iliac,  which  comes  out 
from  under  the  pyriformis,  between  the  lower  edge 
of  that  muscle  and  the  superior  sacro-sciatic  ligament; 
it  lies  upon  the  back  part  of  the  hip,  under  the  gluteus 
maximus; — its  principal  branches  descend  between 
the  trochanter  major  and  tuberosity  of  the  ischium;  it 
sends  other  twigs  round  towards  the  anus  and  peri- 
neum. 

Both  these  arteries  inosculate  with  the  other 
branches  of  the  internal  and  external  iliac. 

The  VEINS  correspond  exactly  to  the  arteries. 
They  terminate  in  the  internal  iliac  vein. 

NERVES. 

NERVUS  SCIATICUS,  vel  ISCHIATICUS,  or  the  Great 
Sciatic  Nerve,  is  seen  coming  out  of  the  pelvis,  along 
with  the  sciatic  artery,  below  the  pyriformis.  It 
descends  over  the  gemini  and  quadratus  femoris  in  the 
hollow  betwixt  the  great  trochanter  and  the  tuberosity 
of  the  ischium , — runs  down  the  back  part  of  the  thigh, 
anterior  to,  i.  e.  nearer  the  bone  than  the  hamstring 
muscles;  being  situated  between  the  anterior  surface 
of  the  semimembranosus,  and  the  posterior  surface  of 
the  triceps  adductor  longus.  After  sending  off  the 
peroneal  nerve,  it  arrives  in  the  ham,  and  becomes 
the  POPLITEAL  NERVE.  In  this  course  it  gives  off 
several  branches  to  the  muscles  and  integuments.  It 
sometimes  perforates  the  belly  of  the  pyriformis  by 
distinct  trunks,  which  afterwards  unite. 


GUIDE   TO   ANATOMY.  205 

DISSECTION  OF  THE  HAM  AND  FASCIA  ON 
THE  BACK  PART  OF  THE  LEG. 

ON  removing  the  integuments  from  the  back  part  of 
the  knee  joint  and  leg,  we  observe  a  FASCIA,  which 
covers  the  great  vessels  and  the  muscles.  It  is  evi- 
dently continued  from  the  great  fascia  of  the  thigh,  is 
strengthened  by  adhesions  to  the  condyles  of  the  femur, 
and  the  head  of  the  fibula,  and  is  prolonged  upon  the 
muscles  on  the  back  of  the  leg. 

Upon  dissecting  back  that  part  of  the  fascia  which 
covers  the  ham,  the  GREAT  SCIATIC  NERVE  appears, 
lying  between  the  outer  and  inner  hamstring  muscles. 
This  nerve,  having  given  off  branches  about  the  ham, 
and  to  the  integuments  on  the  back  of  the  leg,  divides 
at  some  distance  above  the  condyles  of  the  femur  into 
two  large  branches. 

1 .  The  Greater  Nerve  continues  its  course  betwixt 
the  heads  of  the  gastrocnemii  muscles.     In  the  ham 
it  is  named  the  POPLITEAL  NERVE,  and  where  it 
descends  in  the  leg,  the  POSTERIOR  TIBIAL. 

2.  The  Smaller  Nerve,  which  is  the  external  branch, 
is  named  the  PERONEAL  or  FIBULAR  NERVE;  it  passes 
outwards  and  obliquely  downwards,  runs  between  the 
external  head  of  the  gastrocnemius,  and  the  tendon  of 
the  biceps  flexor  cruris;  and  sinks  among  the  muscles 
which  surround  the  head  of  the  fibula. 

BRANCHES  OF  THE  PERONEAL  NERVE. 

(1.)  Cutaneous  branches  are  sent  off  from  the  pero- 
neal  nerve  at  its  uppermost  part  over  the  gastrocne- 
mius to  the  integuments  in  the  back  part  of  the  leg, 
and  outer  side  of  the  foot.  Branches  also  are  distri- 
buted about  the  joint. 

(2.)  A  large  branch,  the  ANTERIOR  TIBIAL  NERVE, 
passes  under  the  flesh  of  the  peroneus  longus  and 
18 


206  LONDON    DISSECTOR,  OR 

extensor  longus  digitorum,  where  those  muscles  arise 
from  the  heads  of  the  fibula  and  tibia;  and  comes  in 
contact  with  the  anterior  tibial  artery,  which  it  accom- 
panies down  the  leg. 

(3.)  Another  branch  passes  into  the  upper  extremity 
of  the  peroneus  longus,  and  is  continued  in  the  substance 
of  that  muscle  for  some  space.  It  then  emerges  from 
beneath  it,  and  continues  its  course  under  the  muscles 
on  the  fore  part  and  outside  of  the  leg;  it  pierces  this 
fascia,  and,  becoming  cutaneous,  is  lost  on  the  ankle 
and  upper  surface  of  the  foot. 

Below  the  great  sciatic  nerve,  there  is  much  cellular 
membrane  and  fat,  which  being  removed,  the  GREAT 
POPLITEAL  VEIN  is  exposed.  It  adheres  to  the  POP- 
LITEAL ARTERY,  which  lies  under  it  close  upon  the 
bone. 

ARTERIA  POPLITEA  is  the  trunk  of  the  FEMORAL, 
which  assumes  that  name,  after  it  has  perforated  the 
tendon  of  the  triceps.  It  lies  between  the  condyles 
of  the  femur,  close  upon  the  bone,  and  descends 
between  the  heads  of  the  gastrocnemius.  It  runs 
over  the  popliteus,  and  under  the  gastrocnemius,  that 
is,  in  the  erect  position  it  is  anterior  to  the  gastroc- 
nemius, and  posterior  to  the  popliteus:  at  the  lower 
edge  of  the  popliteus,  the  popliteal  artery  divides 
into  the  ANTERIOR  and  POSTERIOR  TIBIAL  ARTE- 
RIES. £$ 

BRANCHES. 

1.  Two  PERFORATING  ARTERIES  come  off  from 
the  artery  immediately  after  it  has  entered  the  ham; 
they  are  small,  and  perforate  from  the  ham  to  the 
fore  part  of  the  thigh. 

2.  ARTICULAR  ARTERIES  are  four  or  five  small 
twigs,  ramifying  over  the  knee-joint  and  neighbouring 
muscles,  inosculating  with  one  another,  and  with  the 
arteries  below  the  knee. 


GUIDE    TO    ANATOMY.  207 

3.  Two  branches  are  sent  to  the  two  heads  of  the 
gastrocnemii  muscles;  twigs  are  also  given  to  the 
soleus,  plantaris,  &c. 

The  POPLITEAL  VEIN  receives  branches  corres- 
ponding to  those  of  the  artery;  it  lies  behind  the 
artery  in  the  erect  posture. 

About  two  inches  above  the  condyle,  it  receives 
the  VENA  SAPHENA  MINOR,  which  returns  the  blood 
from  the  outer  side  of  the  foot; — the  trunk  of  this 
vein  lies  under  the  fascia. 


OF  THE  VESSELS  AND  NERVES 

IN  THE  FORE  PART  OF  THE 

LEG   AND    FOOT. 

1.    ARTERIES. 

ARTERIA  TIBIALIS  ANTICA. — The  anterior  tibial 
artery  passes  from  the  ham  betwixt  the  inferior  edge 
of  the  popliteus,  and  the  superior  fibres  of  the  soleus, 
and  then  through  a  large  perforation  in  the  interosse- 
ous  ligament,  to  reach  the  fore  part  of  the  leg;  this 
perforation  is  much  larger  than  the  size  of  the  artery, 
and  is  filled  up  by  the  fibres  of  the  musculus  tibialis 
posticus,  which  may  thus  be  said  to  arise  from  the 
fore  part  of  the  tibia.  The  artery  then  runs  down 
close  upon  the  middle  of  the  interosseous  ligament, 
between  the  tibialis  anticus  and  extensor  proprius 
pollicis;  below  the  middle  of  the  leg,  it  leaves  the  in- 
terosseous ligament  and  passes  gradually  more  for- 
wards; it  crosses  under  the  tendon  of  the  extensor 
proprius  pollicis,*  and  is  then  situated  between  that 

*  It  is  crossed  by  that  tendon  just  abore  the  lower  head  cf  the  tibia, 
while  under  the  annular  ligament. 


208  LONDON    DISSECTOR,  OR 

tendon,  and  the  first  tendon  of  the  extensor  longus 
digitorum:  at  the  ankle  it  runs  over  the  fore  part  of 
the  tibia,  being  now  situated  more  superficially;  then 
over  the  astragalus  and  os  naviculare,  and  over  the 
junction  of  the  os  cuneiforme  internum  and  medium; 
crossing  under  that  tendon  of  the  extensor  brevis  dig- 
itorum which  goes  to  the  great  toe.  Arriving  at  the 
space  between  the  bases  of  the  two  first  metatarsal 
bones,  it  plunges  into  the  sole  of  the  foot,  and  immedi- 
ately joins  the  plantar  arch.  . 

BRA  NCHES: 

1.  A.  RECURRENT,  which  ramifies  over  the  fore 
part  of  the  knee,  inosculating  with  the  articular  arte- 
ries. 

2.  Numerous  twigs  to  the  tibialis  anticus,  extensor 
pollicis,  and  other  muscles  on  the  fore  part  of  the  leg. 

3.  A.  MALLEOLARIS  INTERNA  ramifies  over  the 
inner  ankle,  and  inosculates  with  the  peroneal  and  pos- 
terior tibial  arteries. 

4.  The  EXTERNAL  MALLEOLAR  ramifies  over  the 
outer  ankle. 

5.  The  TARSAL  and  METATARSAL  ARTERIES,  are 
two  small    branches    which  cross   the    tarsal    and 
metatarsal  bones,  and  pass  obliquely  to  the  outer  edge 
of  the  foot. 

From  the  tarsal  or  metatarsal  artery  come  off  the 
INTEROSSEAL  ARTERIES,  which  supply  the  interosseal 
spaces,  and  the  back  part  of  the  toes. 

6.  A  large  branch  comes  off  from  the  anterior  tibial, 
where  it  is  about  to  plunge  into  the  sole  of  the  foot; 
it  runs  along  the  space  betwixt  the  first  two  metatar- 
sal bones,  and  at  the  anterior  extremity  of  those  bones, 
bifurcates  into, 

(1.)  A.  DORSALIS  HALLUCIS,  a  considerable  branch 
which  runs  on  the  back  part  of  the  great  toe. 


GUIDE    TO    ANATOMY.  209 

(2.)  A  branch  which  runs  on  the  inner  edge  of  the 
toe  next  to  the  great  one. 

2.   VEINS. 

The  ANTERIOR  TIBIAL  VEIN  consists  of  two 
branches,  which  accompany  the  artery  and  its  ramifi- 
cations. 

3.    NERVES. 

The  ANTERIOR  TIBIAL  NERVE  is  a  branch  of  the 
peroneal  nerve;  it  is  seen  in  the  ham  arising  from  the 
peroneal,  and  crossing  under  the  muscles  on  the  out- 
side of  the  fibula: — It  emerges  from  under  the  exten- 
sor longus  digitorum,  comes  in  contact  with  the  ante- 
rior tibial  artery,  and  accompanies  it  down  the  leg; 'It 
is  distributed  on  the  back  of  the  foot  and  toes. 


VESSELS   AND   NERVES   OFTHE 

POSTERIOR  PART  OF  THE 

LEG. 

1.    ARTERIES. 

ARTERIA  TIBIALIS  POSTICA.  The  posterior  tibial 
artery,  which  is  the  continued  trunk  of  the  popliteal, 
sinks  under  the  origins  of  the  soleus,  and  runs  down  the 
leg  between  that  muscle  and  the  more  deeply  seated 
flexors  of  the  toes:  It  does  not  lie  in  immediate  con- 
tact with  the  fibres  of  the  flexors,  but,  like  the  femo- 
ral artery,  is  invested  by  a  strong  sheath  of  condensed 
cellular  membrane.  It  is,  together  with  its  veins  and 
accompanying  nerve,  also  supported  by  the  fascia 
which  binds  down  the  deep  seated  muscles.  As  it 
descends,  it  gradually  advances  more  forwards,  fol- 
18* 


210  LONDON    DISSECTOR,    OR 

lowing  the  course  of  the  flexor  tendons:  it  passes  be- 
hind the  inner  ankle,  in  the  sinuosity  of  the  os  calcis, 
lying  posterior  to  the  tendon  of  the  flexor  longus 
digitorum,  and  anterior  to  that  of  the  flexor  longus 
pollicis.  Here  it  is  close  upon  the  bone,  and  in  the 
living  subject  its  pulsation  may  be  felt.  It  sinks  under 
the  abductor  pollicis,  arising  from  the  os  calcis,  and 
immediately  divides  into  two  branches: 

(l.)The^  Internal  Plantar  Artery  is  the  smaller,  and 
ramifies  among  the  mass  of  muscles  situated  on  the 
inner  edge  of  the  sole  of  the  foot. 

(2.)  The  External  Plantar  Artery  directs  its  course 
outwards,  and  having  reached  the  metatarsal  bone  of 
the  little  toe,  forms  the  PLANTAR  ARCH,  which  crosses 
the  three  middle  metatarsal  bones  obliquely,  about 
their  middle,  and  terminates  at  the  space  betwixt  the 
first  two  metatarsal  bones,  where  the  trunk  of  the  an- 
terior tibial  artery  joins  the  arch.  The  convexity  of 
this  arch  is  towards  the  toes,  and  sends  off  the  follow- 
ing branches. 

a,  A  small  branch  to  the  outside  of  the  little  toe. 

6,  Ramus  digitalis  primus,  or  the  first  digital  artery, 
which  runs  along  the  space  between  the  last  two  me- 
tatarsal bones,  and  bifurcates  into  two  branches,  one 
to  the  inner  side  of  the  little  toe,  and  the  other  to  the 
outer  side  of  the  next  toe. 

c,  The  second  digital  artery,  which  runs  along  the 
next  interosseous  space,  and  bifurcates  in  a  similar 
manner. 

d,  The  third  digital  artery. 

e,  The  fourth,  or  great  digital  artery,  which  sup- 
plies the  great  toe,  and  the  inner  side  of  the  toe  next 
to  it. 

The  concavity  of  the  arch  sends  off  the  interos- 
seal  arteries,  three  or  four  small  twigs,  which  go  to 
the  deep-seated  parts  in  the  sole  of  the  foot,  and, 
perforating  between  the  metatarsal  bones,  inosculate 


GUIDE   TO   ANATOMY.  211 

with  the  superior  interosseal  arteries  on  the  upper 
side  of  the  foot. 

The  branches  of  the  Posterior  Tibial  Artery  in  the 
leg  are, 

1.  The  PERONEAL  ARTERY,  which  comes  off  from 
the  tibial  a  little  after  it  has  sent  off  the  anterior  tibial, 
of  which  this  artery  is  sometimes  a  branch;  it  is 
generally  of  a  considerable  size,  sometimes  nearly  as 
large  as  the  tibial  itself;  it  runs  upon  the  inside  of  the 
fibula,   giving  numerous  branches  to  the  peroneal 
muscles  and  flexor  of  the  great  toe;  but  its  course  is 
irregular  and  inconstant.     At  the  lower  part  of  the 
leg,  it  splits  into, 

a,  A.  PERONEA  ANTERIOR,  which  passes  betwixt 
the  lower  heads  of  the  tibia  and  fibula,  to  the  fore- 
part of  the  ankle,  where  it  is  lost. 

fe,  A.  PERONEA  POSTERIOR  is  properly  the  termi- 
nation of  the  artery;  it  descends  along  the  sinuosity 
of  the  os  calcis,  inosculating  with  the  branches  of  the 
tibialis  postica,  and  terminates  in  the  posterior  part 
of  the  sole  of  the  foot. 

2.  Muscular  branches  arise  from  the  artery  as  it 
descends;  twigs  also  are  sent  over  the  heel  and  ankle. 

2.    VEINS. 

VEN^E  TIBIALES  POSTIC^E. — The  posterior  tibial 
veins  are  generally  two  in  number;  they  accompany 
the  artery,  and  terminate  in  the  popliteal  vein;  they 
are  formed  of  branches,  which  correspond  to  those 
of  the  artery. 

3.    NERVES. 

The  POSTERIOR  TIBIAL  NERVE,  which  is  the  con- 
tinuation of  the  great  sciatic  nerve,  sinks  below  the 
soleus,  and  accompanies  the  posterior  tibial  artery;  it 
gives  off  numerous  filaments  to  the  muscles  in  its 
neighbourhood.  At  first  it  continues,  as  in  the  ham, 


212  LONDON    DISSECTOR,  OR 

immediately  behind  the  artery,  but  it  gradually  gets 
on  the  outside  of  it  as  it  descends;  so  that  where 
they  pass  along  the  sinuosity  of  the  os  calcis,  the 
nerve  is  situated  close  in  contact  with  the  side  of  the 
artery,  but  nearer  to  the  projection  of  the  heel  than 
that  vessel  is.  With  the  artery,  it  divides  into, 

1.  The  internal  plantar  nerve,  and, 

2.  The  external  plantar  nerve. — These  nerves  sup- 
ply the  muscles  and  integuments  in  the  sole  of  the 
foot. 


OF  THE  VESSELS  OF  THE  BRAIN. 

THE  arteries  ramify  largely  on  the  pia  mater,  before 
they  enter  the  substance  of  the  brain;  they  come 
from  two  large  branches. 

1.  The  INTERNAL  CAROTID  ARTERY  enters  the 
skull  by  a  winding  course  through  the  foramen  carot- 
icum  of  the  temporal  bone.      After  passing  through 
the  cavernous  sinus,  it  divides  into  three  branches: 
1.  Anterior  cerebri,  passing  between  the  two  anterior 
lobes;  2.  Media  cerebri,  entering  the  fissura  sylvii; 
3.  Ramus  communicans,  uniting  with  the  basilar.  The 
carotid,  while  in  the  cavernous  sinus,  gives  off  the 
arteria  ophthalmica,  which  passes  through  the  fora- 
men opticum  to  the  eye  and  its  appendages. 

2.  The  VERTEBRAL  ARTERY  arises  from  the  sub- 
clavian,  ascends  through  the  foramina  in  the  trans- 
verse processes  of  the  cervical  vertebra,  enters  the 
cranium  by  the  foramen  magnum,  and  gives  branches 
to  the  dura  mater  and  spinal  marrow. — Uniting  with 
its  fellow,  it  forms  the  basilar  artery,  which  gives 
branches  to  the  internal  ear,  branches  to  form  the  cir- 
culus  arteriosus,  and  then  divides  into  two  large 
branches  called  POSTERIORES  CEREBRI,  which  sup- 
ply the  back  parts  of  the  cerebrum. 


GUIDE    TO    ANATOMY.  213 

The  VEINS  pour  their  blood  into  the  sinuses,  which 
are  numerous.  None  of  these  veins  require  particu- 
lar attention,  except  the  ophthalmic  vein,  which 
passes  through  the  foramen  lacerum  orbitale  superius. 
The  principal  sinuses,  viz.  the  longitudinal,  the  two 
lateral,  the  inferior  longitudinal,  &c.  have  been  de- 
scribed in  the  dissection  of  the  brain.  The  remainder 
of  these  sinuses  are  situated  in  folds  of  the  dura 
mater,  but  are  not  regular  in  their  situation.  They 
transmit  their  blood  to  the  longitudinal  and  lateral 
sinuses,  which  terminate  in  forming  the  internal  jugu- 
lar veins. 

For  the  description  of  the  meningeal  arteries 
see  page  98,  and  for  the  nerves  of  the  brain,  see 
page  108. 


OF    THE    VESSELS     AND    NERVES 

SEEN    IN    THE    DISSECTION 

OF    THE   NECK. 

ARTERIES. 

STARTING  from  the  arch  of  the  aorta,  the  student 
will  see  three  large  arteries  coming  off  from  the  up- 
per part  of  that  arch,  viz:  the  arteria  innominata,  the 
left  carotid  and  the  left  subclavian.  From  the  innom- 
inata proceed  the  right  common  carotid,  and  the 
right  subclavian. 

The  carotid  artery  ascends  from  the  thorax  by  the 
side  of  the  trachea;  on  its  outer  side  it  has  the  inter- 
nal jugular  vein,  and  behind  it  the  par  vagum  and  in- 
tercostal nerves.  All  these  parts  are  connected  and 
inclosed  by  condensed  cellular  membrane,  which  forms 
for  them  a  kind  of  sheath.  At  the  bottom,  and  in 
the  middle  of  the  neck,  the  carotid  is  covered  by  the 
sterno-cleido-mastoideus;  at  the  upper  part,  by  adipose 


214  LONDON    DISSECTOR,  OR 

membrane,  absorbent  glands,  and  the  platysma  myoi- 
des.  It  lies  deep  on  the  muscles  of  the  spine,  and 
gives  off  no  branches,  until  it  reaches  the  space  be- 
tween the  larynx  and  the  angle  of  the  jaw,  just  below 
the  cornu  of  the  os  hyoides,  where  it  divides  into  the 
external  and  internal  carotids. 

Of  the  two,  the  internal  carotid  is  situated  more 
outwardly;  it  passes  deep  to  the  base  of  the  cranium, 
where  it  enters  the  foramen  caroticum,  to  supply  the 
brain. 

The  external  carotid  immediately  begins  to  send 
off  branches. 

Anteriorly  it  sends  off, 

1.  The  A.   THYROIDEA  SUPERIOR. — This  artery 
passes  downwards  and  forwards,  to  ramify  on  the 
thyroid  gland,  where  it  inosculates  with  the  artery  of 
the  other  side,  and  with  the  inferior  thyroid  arteries. 
In  this  course,  it  sends  ramifications  to  the  integuments, 
the  outside  of  the  larynx,  the  muscles,  &c.  and  one 
remarkable  branch,  the  A.  LARYNGEA,  which  some- 
times arises  from  the  trunk  of  the  external  carotid;  it 
is  a  small  artery  which  divides  betwixt  the  os  hyoides 
and  thyroid  cartilages,  to  supply  the  internal  parts  of 
the  larynx. 

2.  A.  LINGUALIS,  vel  Ranina. — The  sublingual  ar- 
tery passes  over  the  cornu  of  the  os  hyoides,  then 
behind  the  mylo  hyoideus,  over  the   stylo-glossus, 
hyo-glossus,  and  genio-hyo-glossus,  to  which  it  gives 
branches,  and  terminates  in  running  along  the  inferior 
part  of  the  tongue  from  its  base  to  its  apex.     It  gives 
branches,  to  the  muscles  about  the  chin,  and  to  the 
substance  and  back  part  of  the  tongue. 

3.  A.  MAXILLARIS  EXTERNA. — The  external  max- 
illary artery  passes  under  the  stylo-hyoideus  and  pos- 
terior belly  of  the  digastricus,  then  buries  itself  under 
the  submaxillary  gland.     It  runs  over  the  lower  jaw 
before  the  anterior  edge  of  the  masseter  muscle,  to 
supply  the  face. 


GUIDE   TO    ANATOMY.  215 

In  its  passage,  it  gives  off  numerous  branches. — One 
is  worthy  of  notice,  which  runs  along  under  the  line 
of  the  lower  jaw,  and  passing  over  the  jaw  near  the 
symphysis,  supplies  the  chin.  Other  twigs  supply 
the  submaxillary  gland,  &c. 

Posteriorly  the  carotid  sends  off, 

4.  A.  OCCIPITALIS. — The  occipital  artery  crosses 
backwards  and  upwards,  over  the  internal  jugular 
vein  and  internal  carotid  artery,  under  the  belly  of 
the  digastric  muscle:  it  passes  through  a  slight  groove 
in  the  mastoid  process  below  its  great  fossa,  and  rami- 
fies on  the  back  part  of  the  head.      A  remarkable 
branch  of  the  occipital  passes  towards  the  base  of  the 
skull,  to  inosculate  near  the  foramen  magnum  occipi- 
tis,  with  branches  from  the  vertebral  and  posterior 
cervical  arteries, 

5.  A.  PHARYNGEA  is  a  small  branch  of  the  carotid, 
which  passes  inwards  to  the  pharynx  and  base  of  the 
skull. 

6.  POSTERIOR  AURIS,  which   passes    backwards 
and  upwards  in  the  fold  between  the  ear  and  scalp, 
and  is  distributed  on  the  integuments  of  the  head. 

The  external  carotid  ascends  behind  the  angle  of 
the  jaw,  and  enters  the  parotid  gland,  where  it  divides 
into, 

7.  A.  MAXILLARIS  INTERNA. 

8.  A.  TEMPORALIS. 

9.  A.  TRANSVERSALIS  FACIEI. 

These  arteries  will  be  described  in  the  dissection 
of  the  face. 

VEINS. 

The  INTERNAL  JUGULAR  VEIN  is  a  continuation 
of  the  lateral  sinus  which  passes  through  the  foramen 
lacerum  in  the  base  of  the  cranium.  It  comes  out 
deep  from  under  the  angle  of  the  jaw,  and  in  its  course 
down  the  neck,  it  runs  on  the  outer  side  of  the 


216  LONDON 

carotid  artery,  before  it  reaches  the  thorax;  it  passes 
rather  more  forwards  than  the  artery,  to  join  the  sub- 
clavian  vein. 

Its  branches  accompany  the  ramifications  of  the 
external  carotid.  At  first  the  vein  which  accompa- 
nies each  artery  is  a  single  branch,  but  it  soon  subdi- 
vides, so  that  two  veins  accompany  one  artery. 

NERVES. 

1 .  The  EIGHTH  PAIR,  or  Par  Vagum. — On  sepa- 
rating the  internal  jugular  vein,  and  trunk  of  the  caro- 
tid artery,  the  par  vagum  is  seen  lying  in  the  same 
sheath  of  cellular  substance  with  those  vessels.  It 
lies  in  the  triangular  space  formed  betwixt  the  back 
part  of  the  artery  and  vein,  and  the  subjacent  mus- 
cles. This  nerve  comes  out  of  the  foramen  lacerum 
with  the  jugular  vein;  hence  it  adheres  to  that  vein 
more  closely  than  to  the  artery  or  muscles;  it  runs 
down  the  neck  behind  these  vessels. 

In  this  course  it  gives  off  several  nerves. 

(1.)  At  the  base  of  the  cranium,  it  sends  off  several 
filaments,  which  are  connected  with  the  other  nerves 
coming  out  of  the  base  of  the  skull;  such  as  the  ninth 
pair,  the  superior  cervical  ganglion  of  the  intercos- 
tal, &c. 

(2 .)  NERVUS  GLOSSO-PHARYNGEUS  is  sent  off  from 
the  eighth  pair,  deep  under  the  angle  of  the  jaw.  It 
passes  behind  the  carotids  towards  the  muscles  aris- 
ing from  the  styloid  process;  one  principal  branch  of 
it  passes  between  the  stylo-pharyngeus  and  stylo- 
glossus  to  the  tongue,  while  other  twigs  run  behind 
the  stylo-pharyngeus,  to  supply  the  pharynx.  « 

(3.)  NERVUS  LARYNGEUS  SUPERIOR,  vel  Inter- 
mis. — The  superior  or  internal  laryngeal  nerve  passes 
behind  the  internal  carotid  artery,  obliquely,  down- 
wards and  forwards;  then,  under  the  hyo-thyroideus 


GUIDE    TO    ANATOMY.  217 

muscle,  it  plunges  betwixt  the  os  hyoides  and  thyroid 
cartilage,  accompanying  the  laryngeal  artery,  and 
supplying  the  internal  parts  of  the  larynx. 

(4.)  In  the  neck,  also,  the  par  vagum  gives  off  fila- 
ments to  the  cervical  ganglions  of  the  intercostal 
nerve,  and  to  communicate  with  the  other  nerves  of 
the  neck.  Filaments  also  unite  with  twigs  of  the 
intercostal,  and  run  down  over  the  carotid  artery  to 
the  great  vessels  of  the  heart,  where  they  form  the 
superior  cardiac  plexus. 

The  par  vagum  enters  the  thorax  by  passing  be- 
twixt the  subclavian  artery  and  vein. 

2.  The  INTERCOSTAL,  or  GREAT  SYMPATHETIC 
NERVE. — This  nerve  lies  behind  the  carotid,  in  the 
cellular  membrane,  betwixt  that  vessel  and  the  mus- 
cles covering  the  vertebras  of  the  neck.  It  is  distin- 
guished from  the  par  vagum  by  being  smaller,  lying 
nearer  the  trachea,  and  adhering  to  the  muscles  of  the 
spine;  also  by  its  forming  several  ganglions.  It  arises 
from  the  sixth  pair  in  the  cranium,  and  comes  out  by 
the  same  foramen  as  the  carotid  artery. 

Immediately  after  its  exit  from  the  skull,  it  forms 
the  SUPERIOR  CERVICAL  GANGLION,  which  is  very 
long,  and  of  a  reddish  color.  The  nerve  afterwards 
becomes  smaller,  and  descends;  and  opposite  the  fifth 
or  sixth  cervical  vertebra,  it  forms  another  swelling, 
the  INFERIOR  CERVICAL  GANGLION.  Sometimes  it 
has  another  ganglion  about  the  fourth  or  fifth  vertebra 
of  the  neck,  the  MIDDLE  CERVICAL  GANGLION;  but 
this  is  not  a  constant  appearance.  The  nerve  then 
passes  behind  the  subclavian  artery  into  the  thorax. 

The  branches  of  the  intercostal  nerve  are  nume- 
rous, and  they  generally  pass  off  from  the  ganglions. 
Immediately  below  the  base  of  the  cranium,  twigs  go 
to  the  eighth  and  ninth  pairs,  and  to  the  upper  cervical 
nerves.  In  the  middle  of  the  neck,  some  twigs  pass 
over  the  carotid;  others  go  to  the  parts  covering  the 
19 


218 

trachea,  and  uniting  with  filaments  of  the  par  vagum, 
form  the  external  laryngeal  nerves;  others  unite  with 
the  descendens  noni,  or  descending  branch  of  the  ninth 
pair,  and  some  filaments  assist  the  twigs  of  the  par 
vagum  to  form  the  superior  cardiac  nerve.  In  the 
lower  part  of  the  neck,  twigs  are  sent  to  communicate 
with  the  cervical  nerves,  &c. 

3.  The   NINTH  PAIR,  Nervus  Hypo-glossus,  or 
Lingual  nerve,  having  left  the  skull  by  the  anterior 
condyloid  foramen,  is  connected  with  the  eighth  pair 
and  intercostal  nerve.     Like  them,  it  lies  deep,  and 
comes  out  from  under  the  angle  of  the  jaw.    It  is  seen 
passing  from  behind  the  internal  jugular  vein,  and  then 
over  the  carotid  artery,  running  betwixt  these  two 
vessels.     It  next  passes  under  the  mylo-hyoideus, 
running  over  the  stylo-glossus,  hyo-glossus,  and  genio- 
hyo-glossus,  which  last  muscle  its  numerous  branches 
perforate. 

BRANCHES. — While  the  nerve  is  passing  betwixt 
the  jugular  vein  and  the  carotid  artery,  it  sends  off  the 
DESCENDENS  NONI. — This  small  and  delicate  nerve 
descends  on  the  fore  part  of  the  vein  and  artery,  and 
is  distributed  to  the  muscles  on  the  anterior  part  of 
the  trachea.  It  is  joined  by  filaments  of  the  cervical 
nerves. 

4.  The  LINGUAL  BRANCH  sent  off  by  the  third 
branch  of  the  fifth  pair  of  nerves,  is  also  seen  in  the 
dissection  of  the  neck.  •  It  is  found  under  the  mylo- 
hyoideus;  it  lies  close  upon  the  lower  edge  of  the 
jaw-bone,  betwixt  the  inferior  edge  of  the  pterygoid- 
eus  internus  and  the  upper  part  of  the  mylo-hyoideus. 
It  gives  numerous  twigs  to  the  sublingual  gland  and 
submaxillary  duct,  which  are  situated  near  it,  and  is 
lost  in  the  substance  of  the  tongue. 

5.  NERVUS    ACCESSORIUS  ad  Par  Vagum. — The 
accessory  nerve,  having  passed  out  of  the  cranium 
with  the  par  vagum,  separates  from  it,  passes  behind 


GUIDE   TO   ANATOMY.  219 

the  internal  jugular  vein  obliquely  downwards  and 
backwards;  it  perforates  the  mastoid  muscle,  and  is 
distributed  to  the  trapezius  and  muscles  about  the 
shoulder;  it  is  much  connected  with  the  third  and 
fourth  cervical  nerves. 

6.  The  SEVEN  CERVICAL  NERVES  come  out  from 
the  foramina  betwixt  the  vertebrae  of  the  neck.     They 
send  numerous  branches  to  the  muscles,  &c.,  on  the 
side  of  the  neck,  and  communicate  by  filaments  with 
all  the  other  nerves  in  the  neck. 

In  this  stage  of  the  dissection,  we  may  also  see, 

7.  The  PHRENIC  NERVE,  formed  by  branches  of 
the  third  and  fourth  cervical  nerves.    This  small  nerve 
lies  upon  the  belly  of  the  anterior  scalenus  muscle, 
and  dives  into  the  thorax,  betwixt  the  subclavian 
artery  and  vein. 

8.  The  RECURRENT  NERVE,  a  branch  sent  off  from 
the  par  vagum  in  the  thorax,  is  also  seen  in  the  neck. 
Dissect  between  the  under  surface  of  the  trachea  and 
oesophagus  at  the  lower  part  of  the  neck,  and  you  will 
find  the  recurrent  nerve  situated  there. 

9.  The  upper  part  of  the  GREAT  BRACHIAL  PLEX- 
us  may  be  seen  arising  on  the  side  of  the  neck,  from 
the  lower  cervical  nerves,  and  passing  behind  the  an- 
terior scalenus,  to  reach  the  arm. 

A  general  view  of  the  distribution  of  the  spinal 
nerves  may  be  usefully  subjoined  in  this  place,  to 
complete  the  description  of  the  nerves. 

1.  The  CERVICAL  NERVES  consist  of  seven  pairs; 
they  spread  their  branches  over  the  side  of  the  neck, 
and  to  the  muscles  moving  the  head  and  shoulders. 
The  superior  nerves  send  branches  to  the  side  of  the 
head,  and  the  inferior  to  the  upper  part  of  the  chest 
and  back.  They  also  communicate  freely  with  each 
other,  and  with  all  the  neighboring  nerves;- — high  in 
the  neck,  and  under  the  jaw,  with  the  portio  dura  of 
the  seventh  pair,  with  the  fifth,  eighth,  and  ninth  pairs, 


220  LONDON    DISSECTOR,  OR 

and  with  the  great  sympathetic; — towards  the  middle 
of  the  neck,  with  the  descend  ens  noni,  the  sympathetic 
and  eighth  pair,  and  in  the  lower  part  of  the  neck  with 
the  sympathetic. 

The  PHRENIC  NERVE  is  formed  by  branches  of  the 
third,  fourth,  and  fifth  cervical  nerves,  passes  obliquely 
down  the  neck  through  the  thorax,  then  on  each 
side  of  the  pericardium,  and  is  distributed  to  the  dia- 
phragm. 

The  AXILLARY  PLEXUS  is  formed  by  the  principal 
parts  of  the  trunks  of  the  fourth,  fifth,  sixth,  and 
seventh  cervical,  and  first  dorsal  nerves. 

2.  The  DORSAL  NERVES  are  twelve  pairs.     They 
arise  from  the  spinal  marrow  in  the  same  manner  as 
the  cervical.     Each  nerve  emerges  betwixt  the  heads 
of  the  ribs,  gives  twigs  to  the  great  sympathetic  nerve, 
and  twigs  which  pierce  backwards  to  the  muscles  of 
the  back;  then,  entering  the  groove  in  the  lower  edge 
of  each  rib,  it  accompanies  the  intercostal  artery,  and 
runs  towards  the  anterior  part  of  the  thorax,  supply- 
ing the  great  muscles  of  the  chest,  giving  twigs  to  the 
diaphragm,  and  muscles  of  the  abdomen. 

3.  The  LUMBAR  NERVES  are  five  pairs.     They 

arise  in  the  same  manner;  thoir  trunks  arc  covered  by 

the  psoas  magnus  muscle.  Each  nerve  gives  twigs  to 
the  muscles  of  the  loins  and  back,  and  to  the  sympa- 
thetic nerves,  and  runs  obliquely  downwards  to  supply 
the  abdominal  muscles  and  integuments  of  the  groin 
and  scrotum;  but  the  trunks  of  these  nerves  assist  in 
forming  the  nerves  of  the  thigh. 

4.  The  SACRAL  NERVES  are  five  on  each  side, 
arising  from  the  cauda  equina.  They  come  out  through 
the  anterior  foramina,  and  send  small  branches  to  the 
neighboring  parts;  but  the  great  trunks  of  these  nerves 
are  united  with  the  lumbar  nerves  to  form  the  nerves 
of  the  lower  extremity,  viz. 

(1.)  The  ANTERIOR  CRURAL  NERVE,  passing  out 


GUIDE   TO   ANATOMY. 

under  Poupart's  ligament  to  the  extensor  muscles  of 
the  leg,  is  formed  by  branches  of  the  first,  second, 
third,  and  fourth  lumbar  nerves. 

(2.)  The  OBTURATOR  NERVE,  leaving-  the  pelvis  by 
the  thyroid  holes,  and  being  distributed  to  the  deep 
seated  muscles  on  the  inside  of  the  thigh,  arises  from 
branches  of  the  second,  third,  and  fourth  lumbar 
nerves. 

(3.)  The  ISCHIATIG  or  SCIATIC  NERVE,  the  greatest 
nerve  of  the  body,  passes  out  from  the  back  part  of 
the  pelvis,  through  the  sacro-sciatic  notch,  and  takes 
its  course  along  the  back  of  the  thigh,  to  supply  the 
thigh,  leg,  and  foot;  it  is  formed  from  the  last  two 
nerves  of  the  loins  and  the  first  three  of  the  sacrum. 

All  these  nerves  of  the  spine  communicate  freely  by 
numerous  twigs,  and  by  the  intervention  of 

The  GREAT  SYMPATHETIC  NERVE,  or  INTERCOS- 
TAL. This  nerve,  originally  derived  from  the  sixth 
pair,  arid  from  some  filaments  of  the  fifth,  passes  out 
of  the  cranium  with  the  carotid  artery.  It  then  de- 
scends through  the  neck,  and  forms  three  ganglions  in 
its  course,  which  give  twigs  to  the  neighboring  parts-, 
and  are  joined  by  filaments  from  the  cervical  nerves, 
and  the  eighth  and  ninth  pairs.  The  intercostal  then 
enters  the  thorax,  and  descends  by  the  side  of  the 
vertebrae,  behind  the  pleura,  giving  filaments,  which, 
joining  with  twigs  of  the  eighth  pair,  form  several 
plexuses  to  supply  the  heart,  lungs,  &c.  In  the  ab- 
domen it  descends  on  the  lumbar  vertebras,  and  at  last 
terminates  in  the  pelvis  on  the  extremity  of  the 
coccyx. 

While  in  the  thorax,  it  gives  off  a  branch,  which, 
uniting  with  branches  of  the  dorsal  nerves,  forms 

The  ANTERIOR  INTERCOSTAL,  or  SPLANCHNIC 
NERVE. — This  nerve,  passing  betwixt  the  crura  of  the 
diaphragm,  enters  the  abdomen,  forms  the  semilunar 
19* 


222  LONDON    DISSECTOR,  OR 

ganglion,  and  is  distributed  by  numerous  plexuses  to 
all  the  abdominal  viscera. 

The  Eighth  pair,  or  par  vagum,  has  also  a  very 
long  course;  it  arises  in  the  head,  passes  through  the 
neck,  to  which  it  gives  several  branches.  It  enters 
the  thorax  anterior  to  the  subclavian  artery;  here  it 
gives  off  a  remarkable  branch,  called  the  Recurrent, 
because  it  is  reflected  round  the  arch  of  the  aorta  on  the 
left  side,  and  round  the  subclavian  artery  on  the  right, 
and  ascends  to  be  distributed  on  the  trachea,  oesopha- 
gus, and  larynx.  The  nerve  then  passes  through  the 
thorax,  and,  entering  the  abdomen,  terminates  in  the 
stomach;  in  this  course  it  has  frequent  communications 
with  the  great  sympathetic,  which  it  assists  in  forming 
the  different  plexuses  that  supply  the  thoracic  and 
abdominal  viscera.  It  is  distributed  to  the  heart,  lungs, 
liver,  spleen,  stomach,  and  duodenum. 


COURSE  OF  THE  SUBCLAVIAN 
ARTERY  ON  EACH  SIDE. 

THE  subclavian  artery  passes  upwards  and  out- 
wards, runs  under  the  clavicle,  and  over  the  middle 
of  the  first  rib;  it  passes  between  the  bellies  of  the 
anterior  and  middle  scaleni  muscles,  then  runs  under 
the  arch  of  the  pectoralis  minor,  and  enters  the  axilla, 
where  it  assumes  the  name  of  Axillary  Artery. 

The  order  in  which  the  following  arteries  are  sent 
off  from  the  subclavian  varies  much;  sometimes  they 
come  off  singly,  at  other  times  in  large  trunks,  which 
subdivide. 

Backwards  the  subclavian  sends  off, 

1 .  The  VERTEBRAL  ARTERY. — This  artery  arises 
from  the  back  part  of  the  subclavian,  passes  outwards 
and  enters  the  foramen  in  the  transverse  process  of 


GUIDE   TO   ANATOMY.  223 

the  last  cervical  vertebra,  and  ascends  through  the 
transverse  processes  of  the  vertebrae,  to  enter  the 
foramen  magnum  of  the  occipital  bone. 

2.  The  INFERIOR  THYROID  ARTERY  ascends  ob- 
liquely inwards,  passes  behind  the  internal  jugular 
vein,  to  ramify  on  the  thyroid  gland,  where  it  inos- 
culates largely  with  the  superior  thyroid  arteries. 
Branches  from  this  artery  pass  to  the  trachea  and 
oesophagus,  to  the  muscles  of  the  neck,  and  of  the 
scapula:  one  of  these  is  the  supra  scapulary  artery. 
(See  the  account  of  the  branches  of  the  axillary 
artery.) 

3.  A.  CERVICALIS  ANTERIOR,  vel  Profunda,  passes 
deep  to  the  muscles  situated  on  the  fore  part  of  the 
cervical  vertebras,  and  ascends  as  high  as  the  base  of 
the  skull. 

4.  A.  CERVICALIS   POSTERIOR,  vel   Superficial^, 
is  larger  than  the  last;  it  ascends  obliquely  outwards, 
generally  passes  betwixt  the  transverse  processes  of 
the  last  cervical  and  first  dorsal  vertebrae,  and  ascends 
on  the  back  part  of  the  neck,  deeply  seated;  some  of 
its  branches  pass  down  the  back  superficially. 

Anteriorly,  the  subclavian  artery  gives  off, 

5.  A.  MAMMARIA  INTERNA.     The  internal  mam- 
mary arises  from  the  fore  part  of  the  subclavian,  op- 
posite the  cartilage  of  the  first  rib;  it  runs  down  on  the 
inside  of  the  cartilages  of  the  ribs,  and  terminates  in 
the  abdominal  muscles,  where  it  inosculates  with  the 
epigastric.     It  is  a  large  artery,  and  its  branches  are 
very  numerous.     They  pass  to  the  external  muscles 
of  the  chest,  to  the  intercostal  muscles,  pleura,  &c.  It 
also  sends  off  the  ARTERIA  PHRENICA  SUPERIOR,  vel 
comes  nervi  phrenici,  which,  with  two  veins,  accom- 
panies the  phrenic  nerve  to  the  diaphragm. 

6.  The  subclavian  artery  gives  twigs  to  the  root  of 
the  neck,  and  to  the  muscles  about  the  scapula. 

7.  A.  INTERGOSTALIS  SUPERIOR.     Frequently  a 


224  LONDON    DISSECTOR,  OR 

trunk  comes  off  from  the  subclavian,  especially  on  the 
right  side,  which  passes  downwards  and  backwards, 
and  lodges  itself  by  the  spine,  to  supply  the  two  or 
three  superior  intercostal  spaces. 

COURSE    OF   THE    SUBCLAVIAN    VEIN. 

The  subclavian  vein  is  situated  anteriorly  to  the 
subclavian  artery;  it  passes  inwards  behind  and  under 
the  subclavius  muscle,  and  before  and  over  the  belly 
of  the  anterior  scalenus  (so  that  this  last  muscle  lies 
betwixt  the  vein  and  artery.)  It  runs  over  the  first 
rib,  from  under  the  arch  of  the  pectoralis  minor,  where 
it  is  found  in  contact  with  the  axillary  artery,  and  is 
called  the  Axillary  Vein. 

The  branches  of  this  vein  accompany  and  corres- 
pond to  the  ramifications  of  the  subclavian  artery, 
returning  the  blood  from  the  thyroid  gland,  neck,  chest, 
intercostal  spaces,  &c.  The  subclavian  vein  also 
receives  the  internal  jugular,  which  passes  down  be- 
hind the  clavicle. 

THE    COUR«E    OF  THE   BRACHIAL    PLEXUS    OF  NERVES 

May  also  be  examined.  This  plexus  is  formed  by 
branches  of  the  four  lower  cervical  and  first  dorsal 
nerves,  which  pass  between  the  anterior  and  middle 
scaleni  muscles  into  the  axilla.  In  this  passage  they 
are  situated  higher  up  than  the  artery. 


DISSECTION    OF    THE    AXILLA    OR 
ARM -PIT. 

THERE  is  a  considerable  resemblance  in  the  dis- 
section of  the  axilla  to  that  of  the  ham  or  groin;  in 
each  of  these  situations  we  meet  with  important  blood- 


GUIDE    TO    ANATOMY.  225 

vessels  and  nerves,  closely  connected,  embedded  in 
adipose  membrane,  and  seated  in  the  flexure  of  a 
joint. 

The  axilla  is  formed  by  two  muscular  folds  which 
bound  a  middle  cavity.  The  anterior  fold  is  formed 
by  the  pectoralis  major  passing  from  the  thorax  to 
the  arm,  the  posterior  by  the  latissimus  dorsi  coming 
from  the  back. 

In  the  intermediate  cavity  there  is  a  quantity  of 
cellular  membrane  and  absorbent  glands,  covering 
and  connecting  the  great  vessels  and  nerves.  This 
cellular  and  adipose  membrane  is  continued  from  the 
interstice  above  the  clavicle  betwixt  the  edges  of  the 
trapezius  and  mastoid  muscles.  All  the  space  before 
the  root  of  the  neck  above  the  first  rib,  and  under  the 
clavicle  and  coracoid  process  of  the  scapula,  and  the 
interstices  of  the  muscles  passing  through  that  space, 
are  filled  up  by  a  quantity  of  adipose  membrane;  and 
this  is  not  exactly  similar  to  the  fat  in  other  parts  of 
the  body;  it  is  more  granulated,  watery,  and  of  a 
reddish  color;  it  surrounds  the  great  vessels  and  nerves, 
rendering  the  dissection  both  tedious  and  difficult. 

The  AXILLARY  VEIN  will  be  found  lying  anterior 
to  the  artery,  that  is,  nearer  the  integuments.  It 

Seems  to  be  a  Continuation  of  the  basilic  vein,  which 

runs  along  the  inside  of  the  arm  quite  superficial,  and 
of  the  two  or  three  venae  satellites,  or  veins  which 
accompany  the  brachial  artery.  The  axillary  vein 
receives  branches  corresponding  to  the  ramifications 
of  the  artery.  Passing  under  the  clavicle,  it  becomes 
the  subclavian  vein,  and  runs  over  the  first  rib,  and 
before  the  anterior  scalenus  muscle  into  the  thorax. 

Deeper  seated,  and  immediately  behind  the  axillary 
vein,  lies  the  AXILLARY  ARTERY.  It  is  seen  coming 
from  under  the  clavicle;  from  under  the  arch  formed 
by  the  pectoralis  minor,  it  comes  over  the  middle  of 
the  first  rib,  and  between  the  anterior,  and  middle 


LONDON   DISSECTOR,  OR 

scaleni  muscles.  In  the  axilla  it  is  surrounded  by  the 
meshes  of  the  nerves,  and  runs  along  the  inferior  edge 
of  the  coraco-brachialis  muscle;  when  it  has  passed 
the  anterior  edge  of  the  pectoralis  major,  it  assumes 
the  name  of  the  Brachial  Artery. 

The  branches  of  the  axillary  artery  are, 

1.  A.  MAMMARIA  EXTERNA;  called  also,  A.  Tho- 
racic^   Externae. — The   external  mammary   artery 
consists  of  three  or  four  branches  which  run  down- 
wards and  forwards  obliquely  over  the  chest.     These 
branches   sometimes   come  off  separately  from  the 
axillary  artery,  at  other  times  by  one  or  two  common 
trunks,  which  subdivide.     They  supply  the  pectoral 
muscles  and  mamma.     Some  of  their  branches  pass 
to  the  muscles  of  the  shoulder,  to  the  side  of  the  chest, 
and  to  the  muscles  on  the  inside  of  the  scapula. 

2.  A.  SCAPULARIS  INTERNA,  Supra-scapularis,  or 
Dorsalis  Scapulae,  is  sent  off  from  the  back-part  of 
the  axillary  artery.     It  runs  across  the  bottom  of  the 
neck  towards  the  root  of  the  coracoid  process,  and 
passes  through  the  semilunar  notch  in  the  superior 
costa  of  the  scapula;  it  supplies  the  supra- spinatus 
muscle,  and  then  passes  under  the  acromion,  to  ramify 
on  the  muscles  below  the  spine  of  the  scapula.     It  is 
generally  a  branch  of  the  A.  Thyroidea  Inferior,  and 
is  then  named  A.  Transversalis  Humeri. 

3.  A.  SCAPULARIS  EXTERNA,  INFRA-SCAPULARIS, 
or  Thoracica  Posterior,  arises  from  the  under  and 
back  part  of  the  axillary  artery,  attaches  itself  to  the 
inferior  costa  of  the  scapula,  where  it  splits  into  two 
great  branches:  1 .  A  large  branch,  which  passes  to 
the  outer  surface  of  the  scapula  below  the  spine,  and 
has  its  principal  ramifications  close  upon  the  bone. 
2.  The  other  branch  (which  is  larger)  passes  to  the 
inner  surface  of  the  scapula,  supplies  the  subscapu- 
laris,  and  sends  branches  downwards  to  the  muscles 
of  the  back  and  loins. 


GUIDE    TO   ANATOMY.  221 

4.  ARTERIA  CIRCUMFLEX  A  HUMERI  POSTERIOR, 

Humeralis,  or  Reflexa  Articularis,  arises  from  the 
lower  and  fore  part  of  the  axillary  artery,  and  runs 
backwards  close  to  the  bone,  surrounds  its  neck,  and 
is  lost  on  the  inner  surface  of  the  deltoid;  it  gives 
also  twigs  to  the  joint  and  neighbouring  muscles. 

5.  A.  CIRCUMFLEXA  ANTERIOR  is  a  much  smaller 
artery,  often  a  branch  of  the  circumflexa  posterior; 
it  encircles  the  neck  of  the  bone  on  its  fore-part,  and 
is  lost  on  the  inner  surface  of  the  deltoides,  where  it 
inosculates  with  the  posterior  circumflex  artery. 

The  GREAT  BRACHIAL  NERVES  accompany  the 
subclavian  artery  over  the  first  rib.  In  the  axilla 
they  are  united  by  numerous  cross  branches,  forming 
the  Axillary  or  Brachial  Plexus,  which  is  continued 
from  the  clavicle  as  low  as  the  edge  of  the  tendon  of 
the  latissimus  dorsi,  and  which  surrounds  the  axillary 
artery  with  its  meshes. 

From  the  axillary  plexus  seven  nerves  pass  off. 

1.  NERVUS  SUPRA-SCAPULARIS,  Scapularis  Exter- 
nus,    Scapularis. — This  nerve  comes    off   from  the 
upper  edge  of  the  plexus;  it  crosses  the  axilla  at  the 
highest  part,  runs  towards  the  superior  costa  of  the 
scapula,    accompanies  the   external  scapular  artery 
through  the  semilunar  notch,  and  supplies  the  mus- 
cles on  the  posterior  surface  of  the  scapula. 

2.  N.    CIRCUMFLEXUS,  Articularis,  Axillaris,  or 
Humeralis,  lies  deep:  it  passes  from  the  back  part  of 
the  plexus,  goes  backwards  round  the  neck  of  the 
bone,  accompanying  the  posterior  circumflex  artery, 
and  is  distributed  to  the  musculus  deltoides,  and  the 
muscles  on  the  outside  of  the  arm.      Small  nerves 
also  pass  from  the  axillary  plexus  to  the  subscapular 
muscle,  the  teres  major,  latissimus  dorsi,  and  pecto- 
ral muscles. 

3.  The  External  Cutaneous  Nerve,  or  Nervus- 
Musculo-cutaneus. 


228  LONDON    DISSECTOR,  OR 

4.  The  Radial  Nerve. 

5.  The  Ulnar  Nerve. 

6.  The  Muscular  or  Spiral  Nerve. 

7.  The  Internal  Cutaneous  Nerve. 

These  five  nerves  will  be  described  in  the  dissec- 
tion of  the  arm  and  fore-arm. 


DISSECTION  OF  THE  POSTERIOR  MEDIAS- 
TINUM,* AND  OF  THE  NERVES  AND 
VESSELS  WHICH  HAVE  THEIR 
COURSE  THROUGH  THE 
THORAX. 

COURSE  of  the  PHRENIC  NERVE  through  the  tho- 
rax.— On  each  side  this  nerve  is  seen  entering  the 
thorax  betwixt  the  subclavian  artery  and  subclavian 
vein;  it  then  proceeds  downwards  and  forwards  before 
the  root  of  the  lungs,  and  on  the  outside  of  the  peri- 
cardium, betwixt  that  bag  and  the  plfcura;  and  is  lost 
on  the  diaphragm.  The  left  phrenic  nerve  has  a 
somewhat  longer  course  than  the  nerve  of  the  right 
side,  as  it  passes  over  the  pericardium,  where  that 
bag  covers  the  apex  of  the  heart.  This  nerve  is 
accompanied  by  one  artery  and  two  veins;  some 
twigs  pass  from  the  phrenic  nerve  into  the  abdomen, 
to  the  liver,  &c. 

Behind  the  arch  of  the  aorta  and  great  vessels  pass- 
ing from  the  heart,  is  seen  the  TRACHEA.  It  enters 
the  thorax  between  the  two  pleurae,  and,  opposite  the 
third  or  fourth  dorsal  vertebra,  bifurcates  into  two 
parts:  one  of  which  passes  toward  the  right,  the 
other  toward  the  left,  to  enter  the  lung  of  each  side. 

*  By  Posterior  Mediastinum  is  designed  that  part  of  the  mediastinum 
situated  behind  the  root  of  the  lungs. 


GUIDE    TO    ANATOMY.  229 

By  folding  back  the  lungs  towards  the  left  side  of 
the  chest,  we  expose  the  pleura  reflected  from  the 
under  surface  of  the  root  of  the  lungs  to  the  spine  and 
ribs.  A  triangular  space  is  formed  betwixt  the  two 
pleurae  and  the  bodies  of  the  dorsal  vertebrae;  this 
space  or  cavity  is  named  the  cavity  of  the  posterior 
mediastinum.  It  contains  many  important  parts,  and 
must  therefore  be  carefully  dissected. 

But  first  let  us  attend  to  the  course  of  the  intercos- 
tal, or  great  sympathetic  nerve,  which  is  seen  running 
by  the  side  of  the  spine. 

The  INTERCOSTAL  NERVE,  where  it  enters  the 
thorax,  is  situated  behind  the  great  vessels;  close  upon 
the  articulation  of  the  first  rib  with  the  body  of  the 
first  dorsal  vertebra,  it  forms  a  ganglion,  a  twig  of 
which  fairly  encircles  .the  subclavian  artery,  while 
other  filaments  are  entwisted  round  the  root  of  the 
vertebral  artery.  The  intercostal  nerve  then  descends 
along  the  thorax;  it  lies  upon  the  heads  of  the  ribs,  • 
where  they  are  articulated  with  the  vertebrae;  it  re- 
ceives additional  branches  from  all  the  dorsal  nerves^ 

and  in  each  intercostal  space  it  forms  a  ganglion.  This 
nerve  maybe  dissected  with  greater  facility  when  the 
lungs  are  removed,  and  the  ribs  sawed  oif  near  the  spine, 
which  will  enable  the  dissector  to  trace  its  branches 
more  fully.  It  lies  behind  the  pleura,  but  is  seen 
through  it;  it  passes  into  the  abdomen  by  the  side  of 
the  spine,  running  through  the  fibres  of  the  small 
muscle  of  the  diaphragm. 

BRANCHES  OF  THE  INTERCOSTAL  IN  THE  THORAX. 

The   ANTERIOR    INTERCOSTAL,   or   SPLANCHNIC 

NERVE,  should  be  attended  to.    It  is  formed  by  three 

or  four  twigs,  which  come  off  from  the  intercostal 

betwixt  the  fourth  and  eighth  dorsal  vertebrae;  these 

20 


230  LONDON   DISSECTOR,  OR 

twigs,  passing  forward  on  the  bodies  of  the  vertebrae, 
unite  to  form  the  splanchnic  nerve,  which  may  be 
traced  entering  the  abdomen,  betwixt  the  crura  of  the 
small  muscle  of  the  diaphragm. 

From  the  intercostal  also,  twigs  are  given  off,  which 
assist  the  branches  of  the  par  vagum,  and  of  the  dorsal 
nerves,  in  forming  several  plexuses  to  supply  the  vis- 
cera of  the  thorax. 

The  right  intercostal  nerve  lies  under  the  pleura 
by  the  right  side  of  the  spine.  Still  nearer  the  middle 
of  the  spine,  you  see  the  VENA  AZYGOS.  In  dissect- 
ing it  is  found  situated  betwixt  the  right  intercostal 
nerve  and  the  aorta;  it  begins  below  from  ramifications 
of  the  lumbar  arteries,  which  pierce  the  small  muscle 
of  the  diaphragm.  This  vein  ascends  along  the  spine, 
receiving  veins  from  each  of  the  intercostal  spaces  of 
the  right  side,  and,  about  the  middle  of  the  back,  it 
receives  a  considerable  trunk,  which  comes  from  un- 
.  der  the  aorta,  and  returns  the  blood  from  the  left  side  of 
the  thorax.  At  the  fourth  dorsal  vertebra,  the  vena 
azygos  leaves  the  spine;  it  makes  a  curve  forward, 
and  empties  its  blood  into  the  back  part  of  the  vena 
cava  superior,  immediately  before  that  vein  enters  the 
pericardium. 

Descending  through  the  posterior  mediastinum,  will 
be  also  found  the  AORTA.  This  great  artery,  having 
formed  its  arch,  comes  in  contact  with  the  third  dorsal 
vertebra,  and  is  now  called  the  Descending  Aorta,  or 
Thoracic  Aorta.  It  descends  along  the  bodies  of  the 
dorsal  vertebrae,  rather  on  their  left  side;  it  lies  be- 
hind the  oesophagus,  and  passes  betwixt  the  crura  of 
the  diaphragm  into  the  abdomen. 

BRANCHES  OF  THE  AORTA  IN  THE  THORAX. 

1.  A.  INTERCOSTALES  INFERIORES. — The  arteries 
which  supply  the  three  or  four  superior  intercostal 
spaces,  generally  come  off  in  one  common  trunk,  which 
afterwards  subdivides. 


GUIDE    TO    ANATOMY.  231 

The  Intercostalis  Superior,  on  the  right  side,  is 
mostly  sent  off  by  the  subclavian;  on  the  left  side,  by 
the  aorta. 

The  Inferior  Intercostal s  are  eight  or  nine  in  num- 
ber on  each  side  of  the  thorax;  they  come  off  sepa- 
rately from  the  side  or  back  part  of  the  aorta,  and 
seem  to  tie  that  great  artery  to  the  spine.  Each  in- 
tercostal artery  passes  immediately  into  the  interval 
betwixt  two  ribs,  and  there  subdivides  into, 

(1.)  A  branch  which  perforates  between  the  heads 
of  the  ribs  to  the  muscles  of  the  "back;  this  branch  also 
gives  twigs  which  enter  the  spinal  canal. 

(2.)  The  continued  trunk  of  the  artery  runs  for- 
wards, in  the  interval  of  the  two  ribs,  giving  many 
branches  to  the  intercostal  muscles.  When  it  reaches 
the  anterior  part  of  the  thorax,  it  is  lost  in  the  mus- 
cles. 

Each  intercostal  artery  is  accompanied  by  one  or 
two  veins,  branches  of  the  vena  azygos,  and  by  an 
intercostal  or  dorsal  nerve. 

2.  A.  BRONCHI  ALES  are  two,   sometimes  three^ 
small  twigs  of  the  aorta,  one  of  which  passes  to  the 
lungs  on  each  side;  they  sometimes  arise  from  the 
subclavian  and  superior  intercostal. 

3.  Small  arteries  pass  forwards  from  the  aorta  on 
the  oesophagus,  named  A.  (Esophageae;  others  run  to 
the  pericardium  and  pleura. 

The  dissector  also  finds  in  the  posterior  mediasti- 
num the  THORACIC  DUCT.  He  must  look  for  it  behind 
the  oesophagus,  betwixt  the  vena  azygos  and  aorta;  it 
is  collapsed,  and  appears  like  cellular  membrane  con- 
densed, and  can  only  be  distinguished  when  inflated 
or  injected;  it  was  seen  in  the  abdomen  close  to  the 
aorta,  and  passing  into  the  thorax  between  the  crura 
of  the  diaphragm.  It  ascends  along  the  posterior 
mediastinum,  and,  about  the  fourth  dorsal  vertebra, 
passes  obliquely  to  the  left  side,  behind  the  aorta 


232  LONDON    DISSECTOR,  OR 

descendens,  and  behind  the  great  arch  of  the  aorta, 
until  it  reaches  the  left  carotid  artery.  It  runs  behind 
this  artery,  and  behind  the  left  internal  jugular  vein; 
and,  after  forming  a  circular  turn  or  arch  (the  con- 
vexity of  which  is  turned  upwards,)  it  descends,  and 
enters  the  left  subclavian  vein  at  the  point  where  that 
vein  is  joined  by  the  left  internal  jugular.  In  its 
course  along  the  spine,  the  thoracic  duct  frequently 
splits  into  two  branches,  which  re-unite.  The  absorb- 
ents of  the  right  superior  extremity,  and  of  the  right 
side  of  the  head  and  thorax,  usually  form  a  trunk, 
which  enters  the  right  subclavian  vein. 

The  OESOPHAGUS  is  also  situated  betwixt  the  layers 
of  the  posterior  mediastinum.  It  lies  immediately 
before  the  aorta,  but  rather  towards  its  left  side;  it  is 
seen  descending  from  the  neck  behind  the  trachea;  it 
passes  through  an  opening  in  the  lesser  muscle  of  the 
diaphragm,  and  immediately  expands  into  the  stomaoh. 

Behind  the  trachea  and  vessels  going  to  the  lungs, 
and  on  the  fore  part  of  the  oesophagus,  we  meet  with 
a  congeries  of  lymphatic  glands. 

COURSE    OF    THE    PAR    VAGUM,    OR    EIGHTH    PAIR    OF 


From  the  neck,  the  par  vagum  passes  betwixt  the 
subclavian  vein  and  artery  into  the  thorax;  it  imme- 
diately sends  off  a  large  branch,  the  RECURRENT 
NERVE,  back  into  the  neck.  On  the  right  side,  this 
branch  twists  round  under  the  arteria  innominata;  on 
the  left  side,  under  the  arch  of  the  aorta,  it  ascends 
behind  the  carotid,  and  lodges  itself  betwixt  the  tra- 
chea and  oesophagus,  to  both  of  which  it  gives  branches. 

The  par  vagum,  having  given  off  the  recurrent, 
descends  by  the  side  of  the  trachea,  and  behind  the 
root  of  the  lungs.  It  here  sends  off  numerous  fila- 
ments to  the  lungs,  which,  uniting  with  twigs  from 


GUIDE    TO    ANATOMY.  233 

the  great  sympathetic,  form  the  ANTERIOR  and  POS- 
TERIOR PULMONARY  PLEXUSES;  these  plexuses  lie  on 
the  anterior  and  posterior  surfaces  of  the  root  of  the 
lungs.  Other  twigs  of  the  par  vagum  pass,  to  form 
the  inferior  CARDIAC  PLEXUS  ahout  the  pericardium. 

The  trunk  of  the  eighth  pair  soon  reaches  the  oeso- 
phagus; the  left  par  vagum  runs  on  the  fore  part  of  the 
oesophagus,  the  right  nerve  on  its  back  part.  Here 
they  split  into  several  branches,  which  unite  again, 
and  form  a  PLEXUS.  This  plexus  is  called  the  (ESOPHA- 
GEAL.  The  two  nerves  continue  their  course  along  the 
resophagus,  and  pass  with  it  through  the  diaphragm, 
to  ramify  on  the  stomach,  and  form  the  stomachic 
plexus. 

The  twelve  dorsal  or  intercostal  jierves  are  also 
seen  in  this  dissection,  emerging  from  the  spinal  canal, 
between  the  bodies  of  the  vertebras,  and  supplying 
the  intercostal  muscles,  &c. 


OF    THE    VESSELS    AND    NERVES] 
OF    THE    FACE. 

ARTERIES. 

THE  A.  MAXILLARIS  EXTERNA,  the  third  branch 
of  the  carotid,  comes  from  the  neck  over  the  lower 
jaw  at  the  anterior  edge  of  the  masseter.  It  then  runs 
under  the  depressor  anguli  oris,  passes  towards  the 
angle  of  the  mouth,  and  is  often  much  contorted.  Here 
it  i%named  the  A.  Facialis  or  Angularis.  It  ascends 
by  the  side  of  the  nose,  and,  reaching  the  inner  angle 
of  the  eye,  is  lost  on  the  muscles  situated  there,  inos- 
culating freely  with  the  temporal,  internal  maxillary, 
and  ophthalmic  arteries.  In  this  course  it  gives  off 
many  branches:  1.  Twigs  to  the  masseter,  depressor 
20* 


234  LONDON   DISSECTOR,  OR 

anguli  oris,  and  chin;  2.  A.  CORONARIA  LABIORUM. 
This  artery  is  very  much  contorted. — At  the  angular 
commissure  of  the  lips,  it  divides  itself  into  two 
branches,  which  run  along  the  superior  and  inferior 
portions  of  the  orbicularis  oris,  and  join  the  same 
branches  of  the  other  side.  3.  While  the  facial 
artery  ascends  by  the  side  of  the  nose,  it  gives  off  the 
external  nasal  arteries  lo  the  outside  of  the  nose,  and 
the  A.  Buccales  to  the  cheek. 

The  External  Carotid  is  found  ascending  behind 
the  parotid  gland.  It  perforates  the  gland  at  its  upper 
part,  ascends  over  the  zygomatic  process  immediately 
before  the  ear,  and  divides  into  the  anterior,  middle, 
and  posterior  temporal  arteries,  which  ramify  over 
the  side  of  the  head,  giving  also  branches  to  the  fore- 
head and  occiput. 

But  the  carotid,  while  it  lies  embedded  under  the 
parotid,  sends  several  twigs  to  the  substance  of  that 
gland,  and  a  considerable  artery  which  passes  for- 
wards, and,  ramifying  on  the  side  of  the  face,  is  named 
A.  TRANSVERSALIS  FACIEI.  At  this  point  also,  the 
carotid  sends  off  a  large  artery,  the  A.  MAXILLARIS 
INTERN  A.  As  many  branches  of  this  artery  are  met 
with  in  the  dissection  of  the  face,  it  is  proper  to  give 
a  view  of  its  distribution. 

The  Internal  Maxillary  passes  behind  the  condyloid 
process  of  the  lower  jaw:  it  directs  its  course  towards 
the  bottom  of  the  orbit  of  the  eye;  and  it  is  at  this  point 
that  it  sends  off  its  numerous  branches.  (1 .)  ARTERI A 
MEDIA  DUR^  MATRIS  (or  Meningea  spheno-spinalis 
or  spinosa)  passes  through  the  spinal  hole  of  the  sphe- 
noid bone  into  the  cranium,  and  is  distributed  to*  the 
dura  mater.  (2.)  A.  MAXILLARIS  INFERIOR,  vel 
Dentalis  Inferior,  runs  downwards,  enters  the  foramen 
at  the  root  of  the  ascending  processes  of  the  lower 
jaw;  then  passes  through  the  canal  of  the  lower  jaw, 
supplying  the  teeth  and  sockets,  and  emerges  by  the 


GUIDE    TO    ANATOMY.  235 

foramen  mentale,  to  be  distributed  to  the  chin.  It  is 
accompanied  by  a  nerve  and  one  or  two  veins.  (3.) 
A.  Pterygoideae  and  A.  Temporales  Profunda3,  are 
small  branches  of  the  internal  maxillary  which  pass 
to  the  pterygoid  muscles,  and  to  the  inner  part  of  the 
temporal  muscle.  (4.)  A.  Pharyngeae,  branches  to  the 
pharynx,  palate,  and  base  of  the  skull.  (5.)  A.  Alve- 
olaris,  which  gives  branches  to  the  teeth  of  the  upper 
jaw,  and  to  the  jaw-bone  itself.  (6.)  A  Branch  through 
the  foramen  spheno-palatinum  to  the  nose;  and,  (7.) 
An  Artery  through  the  palato-maxillary  canal  to  the 
palate. 

The  continued  trunk  of  the  internal  maxillary  enters 
the  orbit  by  the  spheno-maxillary  slit.  It  sends  off  a 
branch  which  runs  along  the  inner  side  of  the  orbit, 
and  passes  out  at  the  inner  canthus  of  the  eye  on  the 
forehead.  The  artery  itself  runs  along  the  bottom  of 
the  orbit  in  a  canal  on  the  upper  part  of  the  great 
tuberosity  of  the  os  maxillare  superius,  and  emerges 
by  the  foramen  infra-orbitarium  on  the  face;  hence  it 
is  termed  A.  Infra-Orbitaria,  and  is  distributed  to  the 
cheek  and  side  of  the  nose. 

The  FRONTAL  ARTERY  is  also  seen  in  the  dissection 
of  the  face,  passing  from  the  orbit  through  the  foramen 
supra-orbitarium  to  be  distributed  to  the  forehead. 
This  artery  is  sent  off  from  the  ophthalmic  artery, 
which  is  a  branch  of  the  internal  carotid. 

If  the  face  be  injected,  a  remarkable  anastomosis 
of  arteiies  will  be  observed  at  the  inner  angle  of  the 
eye. 

VEINS. 

The  veins  of  the  face  are  numerous,  and  pass  into 
the  external  and  internal  jugular  veins. 


236  LONDON    DISSECTOR,  OR 


NERVES. 

1.  The  PORTIO  DURA  of  the  seventh  pair,  Nervus 
Communicans  Faciei,  or  Facial  Nerve,  after  its  course 
through  the  temporal  bone  in  the  aqueduct  of  Fallopius, 
comes  out  by  the  foramen  stylo-mastoideum.      It 
immediately  gives  off  branches  to  the  neighboring 
parts,  as  behind  the  ear.     It  then  passes  through  the 
substance  of  the  parotid  gland,  and  emerges  on  the 
face  in  three  great  branches,  which  have  frequent 
mutual  communications:  this  division  of  the  nerve  is 
called  PES  ANSERINUS. 

(1.)  The  ascending  branch  ramifies  on  the  temple 
and  forehead. 

(2.)  The  middle  branch  sends  its  ramifications  over 
the  side  of  the  face,  the  proper  Facial  Nerves. 

(3.)  The  descending  branch  sends  its  twigs  along 
the  chin,  down  upon  the  neck,  and  backwards  upon 
the  occiput. 

2.  The  SUPERIOR   CERVICAL  NERVES  send  off 
several  branches,  which  ramify  on  the  side  of  the  face 
and  head,  and  communicate  freely  with  the  branches 
of  the  portio  dura. 

As,  in  the  course  of  this  dissection,  we  meet  with 
many  twigs  of  the  second  and  third  branches  of  the 
fifth  pair  of  nerves,  it  will  be  advisable  here  to  describe 
these  nerves. 

3.  NERVUS  MAXILLARIS    SUPERIOR,  or  Second 
Branch  of  the  Fifth  Pair.     The  superior  maxillary 
nerve,  having  left  the  cranium  by  the  foramen  rotun- 
dum  of  the  sphenoid  bone,  emerges  behind  the  antrum 
maxillare,  at  the  lower  back  part  of  the  orbit,  and  at 
the  root  of  the  pterygoid  process  of  the  sphenoid  bone. 
It  immediately  sends  out  branches:  1 .  A  small  branch 
which  passes  through  the  spheno-maxillary  slit  to  the 
periosteum  and  fat  of  the  orbit.     2.   The  largest 
branch  is  the  INFRA-ORBITARY  NERVE.     It  enters 


GUIDE    TO    ANATOMY.  237 

the  channel  in  the  top  of  the  antrum  maxillare,  accom- 
panying the  infra-orbitary  artery,  comes  out  at  the 
foramen  infra-orbitarium,  and  is  widely  distributed  to 
the  cheek,  under  lip,  and  outside  of  the  nose,  commu- 
nicating with  ramifications  of  the  portio  dura.  3. 
Branches  to  the  temporal  muscle,  os  malae,  £c.  4. 
Other  branches  form  a  small  ganglion  at  the  root  of 
the  orbit,  which  sends  twigs,  named  the  superior  Nasal 
Nerves,  through  the  foramen  spheno-palatinum  to  the 
nose.  5.  The  Vidian  Nerve,  which  enters  the  fora- 
men pterygoideum,  and  passes  again  into  the  cranium, 
to  connect  itself  with  the  portio  dura.  6.  The  Pala- 
tine Nerve,  which  runs  through  the  palato-maxillary 
canal  to  the  palate.  7.  Twigs  which  supply  the  gums 
and  alveoli  of  the  upper  jaw. 

4.  NERVUS  MAXILLARIS  INFERIOR,  or  Third 
Branch  of  the  Fifth  Pair.  The  inferior  maxillary 
nerve  leaves  the  cranium  by  the  foramen  ovale  of  the 
sphenoid  bone.  It  has  its  course  downwards  and  out- 
wards; and,  having  given  twigs  to  the  parts  near  which 
it  passes,  as  the  masseter,  pterygoid,  and  temporal 
muscles,  it  divides  at  the  angle  of  the  lower  jaw  into 
two  branches.  1.  The  Nervus  Dentalis  Inferior 
enters  the  foramen  at  the  angle  of  the  lower  jaw; 
accompanies  the  inferior  dental  artery  along  the  canal 
in  that  bone,  giving  nerves  to  the  teeth;  emerges  by 
the  foramen  mentale,  and  is  distributed  to  the  chin. 
2.  The  Nervus  Gustatorius,  vel  Lingualis,  passes  to 
the  tongue.  It  was  seen  in  the  dissection  of  the  neck 
lying  close  upon  the  lower  jaw-bone,  below  the  infe- 
rior edge  of  the  pterygoideus  internus,  and  above  the 
superior  fibres  of  the  mylo-hyoideus.  It  supplies  the 
substance  of  the  tongue,  and  the  salivary  glands  situ- 
ated at  the  root  of  the  tongue. 

This  nerve  receives  the  chorda  tympani,  a  small 
twig  which  comes  from  the  seventh  pair  through  the 
slit  in  the  articulating  cavity  of  the  temporal  bone. 


238  LONDON   DISSECTOR,  OR 

5.  In  the  dissection  of  the  face,  we  also  meet  with 
the  FRONTAL  NERVE;  which  comes  from  the  first 
branch  of  the  fifth  pair,  and  which  is  seen  accompany- 
ing the  frontal  artery  through  the  foramen  supra-orbi- 
tarium.  It  is  distributed  to  the  forehead. 


OF    THE    VESSELS    AND    NERVES 

MET    WITH   IN    THE   ORBIT 

OF    THE    EYE. 

ARTERIES. 

THE  OPHTHALMIC,  or  OCULAR  ARTERY,  is  a  branch 
of  the  internal  carotid.  It  enters  the  orbit  from  the 
basis  of  the  cranium  by  the  foramen  opticum.  It  gives 
branches  to  the  lachrymal  gland,  fat,  muscles,  and 
globe  of  the  eye.  One  twig,  named  the  A.  Centralis 
Retinae,  enters  the  substance  of  the  optic  nerve,  and 
is  continued  on  to  the  retina; — twigs  also  pass  to  the 
eye-lids,  and  to  the  inner  angle  of  the  eye.  The  Ar- 
teria  Frontalis  is  a  branch  of  this  artery;  it  is  seen 
running  towards  the  supra-orbitary  notch  or  foramen, 
and  is  distributed  to  the  forehead. 

The  INFRA-ORBITARY  ARTERY  is  found  in  the 
lower  part  of  the  orbit;  it  is  the  continued  trunk  of 
the  internal  maxillary,  entering  the  orbit  by  the  sphe- 
no-maxillary  slit.  It  is  seen  passing  along  the  canal 
in  the  upper  part  of  the  great  tuberosity  of  the  os 
maxillare  superius,  and  emerges  on  the  face  by  the 
infra-orbitary  hole. 

VEINS. 

These  correspond  with  the  arteries;  they  discharge 
their  blood  partly  into  the  branches  of  the  external 
jugular  vein  near  the  forehead  and  temples,  and  partly 
into  the  internal  jugular. 


GUIDE    TO    ANATOMY.  239 


NERVES. 

1 .  The  OPTIC  NERVE  is  seen  coming  through  the 
foramen  opticum,  and  entering  the  back  part  of  the 
globe  of  the  eye,  to  form  the  retina. 

2.  The  Nerve  of  the  Third  Pair,  MOTOR  OCULI, 
having  entered  the  orbit  through  the  superior  orbi- 
tary  fissure,  or  foramen  lacerum,  is  divided  into  four 
branches. 

(1.)  The  first  runs  upwards,  and  subdivides  into 
two  nerves,  of  which  one  supplies  the  levator  oculi, 
and  the  other  the  levator  palpebrae  superioris. 

(2.)  The  second  branch  goes  to  the  depressor  oculi, 
and  is  short. 

(3.)  The  third  branch  supplies  the  obliquus  inferior, 
and  also  gives  off  a  twig,  which  assists  in  forming  the 
lenticular  ganglion. 

(4.)  The  fourth  branch  supplies  the,  adductor  oculi. 

3.  The  Nerve  of  the  Fourth  Pair,  N.  PATHETICUS, 
or  Trochlearis,  enters  the  orbit  by  the  superior  orbi- 
tary  fissure,  and  runs  to  the  obliquus  superior. 

4.  The  first  branch  of  the  Nerve  of  the  Fifth  Pair, 
named  OPHTHALMIC,  or  Orbitary,  enters  the  orbit  by 
the  superior  orbitary  fissure,  and  divides  into  three 
branches. 

(1.)  The  FRONTAL,  Supra-orbitary,  or  Superciliary 
Nerve,  accompanies  the  frontal  artery  along  the  upper 
part  of  the  orbit,  close  to  the  bone;  and  having  passed 
through  the  supra-orbitary  notch,  is  distributed  to  the 
forehead. 

(2.)  The  NASAL  Nerve,  or  inner  branch,  runs  to- 
wards the  nose,  and  is  distributed  to  the  inner  side  of 
the  orbit,  and  to  the  nose. 

(3J  The  Temporal  or  Lachrymal  Branch  supplies 
the  lachrymal  gland,  and  the  parts  at  the  outer  side  of 
the  orbit. 

The  LENTICULAR  GANGLION  is  a  small  ganglion. 


240  LONDON    DISSECTOR,  OR 

situated  within  the  orbit,  formed  by  short  branches  of 
the  ophthalmic  nerve,  and  by  a  twig  of  the  third  pair. 
It  sends  off  delicate  nerves  which  run  along  the  sides 
of  the  optic  nerve,  and  pierce  the  coats  of  the  eye. 

5.  The  second  branch  of  the  Fifth  Pair,  called  the 
SUPERIOR  MAXILLARY  NERVE,  sends  off  a  branch 
through  the  bony  canal  in  the  bottom  of  the  orbit. 
This  is  the  INFRA-ORBITARY  NERVE.    It  accompanies 
the  artery  of  the  same  name,  and  emerges  on  the  face 
by  the  infra-orbitary  hole. 

6.  The  Trunk  of  the  Sixth  Pair  of  Nerves  passes 
through  tlie  superior  orbitary  fissure  to  the  abductor 
oculi. 

These  delicate  nerves  are  surrounded  by  the  adi- 
pose substance  found  in  the  orbit,  and  require  to  be 
dissected  with  the  utmost  care. 


DISSECTION   OF  THE   CUTANEOUS 

VESSELS    AND  NERVES   OF   THE 

SHOULDER   AND    ARM. 

IN  removing  the  integuments,  we  meet  with  several 
cutaneous  veins  and  nerves. 

The  cutaneous  veins*  of  the  upper  extremity  are 
the  following. 

1 .  The  BASILIC  VEIN  is  seen  arising  from  a  small 
vein  on  the  outside  of  the  little  finger,  named  Salva- 
tella.  It  then  runs  along  the  inside  of  the  fore  arm 
near  the  ulna,  receiving  the  internal  and  external  .ulnar 
veins  from  the  anterior  and  posterior  surface  of  the 
fascia.  It  passes  over  the  fold  of  the  arm  near  the 
inner  condyle  of  the  humerus;  here  it  is  superficial. 

*  The  reins  are  described  from  their  origin  in  the  fore  arm,  for  the 
Sake  of  perspicuity;  they  ramify  above  the  fascia  of  the  fore  arm. 


GUIDE    TO    ANATOMY.  241 

It  ascends  along  the  arm,  becoming  more  deeply  seat- 
ed, and  included  in  the  sheath  which  invests  the 
brachial  artery.  As  it  approaches  the  neck  of  the 
humerus,  it  sinks  deep  betwixt  the  folds  of  the  arm- 
pit, and  terminates  in  the  axillary  vein,  which  may  be 
considered  as  a  continuation  of  the  basilic  vein.  It 
communicates  with  the  deeper-seated  veins,  and 
receives  numerous  branches  from  the  muscles. 

2.  The  CEPHALIC  VEIN  begins  on  the  back  of  the 
hand,  between  the  thumb  and  metacarpal  bone  of  the 
fore-finger,  by  a  small  vein,  named  Cephalica  Pollicis. 
It  runs  along  the  radius  between  the   muscles   and 
integuments,  receiving  the  internal  and  external  radial 
veins.     It  passes  oyer  the  bend  of  the  arm  near  the 
external  condyle,  and  ascends  along  the  outside  of  the 
arm  near  the  outer  edge  of  the  biceps  flexor  cubiti. 
It  then  runs  betwixt  the  edge  of  the  deltoid  and  pec- 
toral muscles,  dips  down  under  the  clavicle,  and  enters 
the  subclavian  vein.     In  all  this  course,  the  cephalic 
vein  receives  branches. 

3.  The  MEDIAN   VEIN.     Several  veins  are  seen 
running  along  the  middle  of  the  anterior  part  of  the 
fore-arm.     The  trunk  formed  by  these  veins  is  called 
the  Mediana  Major.     It  ascends  on  the  flat  part  of  the 
fore  arm,  betwixt  the  basilic  and  cephalic  veins,  and 
bifurcates  at  the  fold  of  the  arm  into  two  branches: 
1 .  The  Mediana  Basilica,  passing  off  obliquely  to  join 
the  basilic  vein;    2.  The  Mediana  Cephalica,  which 
joins  the  cephalic. 

The  cutaneous  nerves  of  the  arm  are  seen  ramifying 
above  the  muscles;  they  consist  of, 

1 .  The  Internal  Cutaneous  Nerve,  a  branch  of  the 
axillary  plexus.  It  is  seen  accompanying  the  basilic 
vein,  and  twisting  its  fibres  over  it.  It  descends  along 
the  inside  of  the  arm,  crosses  over  the  fore  part  of 
the  elbow-joint,  and,  in  the  dissection  of  the  fore  arm, 
will  be  seen  dividing  itself  into  twigs,  which  ramify 
21 


242  LONDON    DISSECTOR,    OR 

between  the  fascia  and  integuments,  and  are  distri* 
buted  to  the  inside  of  the  fore  arm  and  wrist. 

2.  The  upper  part  of  the  arm  receives  cutaneous 
nerves  from  the  branches  of  the  dorsal  nerves,  which 
come  out  of  the  thorax  between  the  ribs. 

3.  The  shoulder  and  back  part  of  the  scapula 
receive  twigs  from  the  cervical  nerves. 

4.  The  external  cutaneous,  ulnar,  and  spiral  nerves, 
also  send  twigs  to  the  integuments  of  the  arm  and 
fore  arm. 

The  relative  situation  of  the  vessels  at  the  bend  of 
the  arm  should  be  well  attended  to.  The  cutaneous 
veins  situated  here  vary  much  in  size.  The  vena 
basilica  is  seen  running  over  the  fore  part  of  the  bend 
of  the  arm  near  the  inner  condyle,  the  vena  cephalica 
situated  near  the  outer  condyle;  and  each  of  these 
veins  receives  a  branch  passing  obliquely  from  the 
vena  mediana  major.  These  vessels  lie  above  the 
fascia,  while  the  brachial  artery  lies  deep  beneath  the 
fascia,  in  a  hollow  resembling  that  of  the  axilla.  It 
descends  over  the  joint  near  the  inner  condyle,  on  the 
inside  of  the  tendon  of  the  biceps  flexor  cubiti,  and 
under  the  aponeurosis  sent  off  from  that  muscle  to  the 
common  fascia  of  the  fore  arm.  It  lies  embedded  in 
cellular  substance,  betwixt  the  pronator  teres  and 
flexor  muscles  of  the  wrist  and  fingers  on  one  side, 
and  the  supinator  longus  and  extensor  muscles  on  the 
other.  In  this  hollow  it  divides  into  the  radial,  ulnar, 
and  interosseal  arteries.  The  artery  is  accompanied 
by  two  veins,  and  on  its  inner  side  runs  the  radial 
nerve. 


t 


GUIDE  TO  ANATOMY.  243 

OF  THE  VESSELS  AND  NERVES  OF 
THE  SUPERIOR  EXTREMITY. 

ARTERIES. 

THE  subclavian  and  axillary  arteries  have  already 
been  described. 

The  BRACHIAL  ARTERY  may  be  said  to  have  its 
course  along  the  inside  of  the  arm.  Having  left  the 
axilla,  it  runs  along  the  inferior  edge  of  the  coraco- 
brachialis.  Rather  higher  up  than  the  middle  of  the 
os  humeri,  it  crosses  over  the  tendinous  insertion  of 
that  muscle,  being  here  situated  between  the  belly  of 
the  biceps  flexor  cubiti,and  the  superior  fibres  of  the 
brachialis  externus.  The  artery  then  passes  behind 
the  inner  edge  of  the  biceps  flexor  cubiti,  descending 
betwixt  that  muscle  and  the  fibres  of  .the  brachialis 
internus.  In  dissecting  this  vessel,  we  find  it  invested 
by  a  fascia  or  sheath,  formed  by  cellular  membrane 
and  some  tendinous  fibres.  This  fascia  may  be  traced 
extending  from  the  internal  intermuscular  ligament. 
It  covers  the  brachial  artery  and  radial  nerve;  and  the 
great  basilic  vein,  as  it  enters  into  the  axilla,  is  found 
lying  in  the  fore  and  inner  part  of  this  sheath.  It 
supports  and  connects  these  vessels.  On  dissecting 
this  fascia,  we  find,  close  to  the  margin  of  the  coraco- 
brachialis  and  biceps  flexor  cubiti,  the  great  radial 
nerve;  under  it  the  brachial  artery;  and,  more  super- 
ficially seated,  the  venae  comites  and  the  vena  basilica. 
As  the  artery  approaches  the  lower  extremity  of  the 
os  humeri,  it  inclines  forwards  toward  the  fold  of  the 
arm,  and  dives  beneath  the  aponeurosis  which  arises 
from  the  inside  of  the  tendon  of  the  biceps  flexor 
cubiti.  Its  situation  at  the  fold  of  the  arm  has  been 
described. 


244  LONDON    DISSECTOR,  OR 


BRANCHES    OF   THE    BRACHIAL    ARTERY. 

.  1.  A.  PROFUNDA  HUMERI  SUPERIOR,  or  Muscu- 
laris  Superior,  is  sent  off  from  the  inner  side  of  the 
brachial  artery,  immediately  where  it  has  left  the  fold 
of  the  arm-pit.  It  passes  downwards  and  backwards 
round  the  os  humeri,  and  is  accompanied  by  the 
muscular  or  spiral  nerve.  It  passes  betwixt  the 
brachialis  externus  and  short  head  of  the  triceps 
extensor  cubiti.  Here  it  lies  deep  among  the  muscles, 
and  divides  into  two  branches.  One  accompanying 
the  nerve  spreads  its  ramifications  over  the  outer 
condyle,  and  anastomoses  with  the  arteries  below  the 
elbow.  The  other  branch  is  distributed  along  the 
inside  of  the  arm,  and  about  the  inner  condyle. 

2.  A.  PROFUNDA  HUMERI  INFERIOR,  vel  Minor, 
or  Muscularis  Inferior,  is  smaller  than  the  last,  and  is 
sent  off  from  the  brachial  artery  about  two  inches 
lower  down.  It  descends  among  the  muscles  on  the 
inside  of  the  arm,  and  is  lost  about  the  inner  condyle. 
'  3.  The  anastomosing  or  collateral  arteries  are  as 
follows. 

(1.)  The  Ramus  Anastomoticus  Major  passes  from 
the  inside  of  the  brachial  artery,  about  two  or  three 
inches  above  the  inner  condyle.  It  is  distributed 
about  the  condyle;  and  its  principal  branch  accom- 
panies the  ulnar  nerve  in  the  groove  betwixt  the 
olecranon  and  inner  condyle,  to  anastomose  with  the 
recurrent  branches  of  the  arteries  of  the  fore-arm. 

(2.)  There  are  two  or  three  more  anastomosing 
branches,  which  are  sent  off  from  the  brachial  artery, 
and  ramify  over  the  anterior  and  posterior  surfaces  of 
the  two  condyles. 

4.  Small  branches  to  the  muscles  of  the  arm. 

The  Brachial  Artery,  where  it  lies  deep  under  the 
aponeurosis  of  the  biceps,  divides  into  three  branches. 
1.  The  radial;  2.  The  ulnar;  and,  3.  The  interosse- 


GUIDE    TO    ANATOMY.  245 

ous  artery.     The  last  two  generally  come  off  by  one 
trunk,  which  subdivides. 

1 .  ARTERIA  RADIALIS,  the  radial  artery,  is  smaller 
than  the  ulnar,  and  in  its  course  more  superficial.  It 
leaves  the  ulnar  artery,  and  inclines  towards  the  radial 
or  outer  edge  of  the  fore-arm.  At  first  it  lies  betwixt 
the  pronator  teres  and  supinator  longus.  It  then 
descends  close  along  the  inner  edge  of  the  supinator 
longus,  and  about  the  middle  of  the  fore-arm  passes 
over  the  insertion  of  the  pronator  teres.  It  then  holds 
its  course  betwixt  the  supinator  longus  and  flexor 
carpi  radialis,  and  is  accompanied  by  a  branch  of  the 
muscular  or  spiral  nerve.  In  this  situation  the  artery 
continues  its  course  along  the  radius,  till,  reaching  the 
lower  extremity  of  that  bone,  it  divides  into  two 
branches. 

(1.)  Ramus  Volaris,  A.  SUPERFICIALIS  VOLJE,  is 
by  much  the  smaller  of  the  two  branches.  It  passes 
into  the  muscular  mass  which  forms  the  ball  of  the 
thumb,  and  spreads  its  ramifications  on  the  palmar 
fascia,  the  annular  ligament  of  the  wrist,  and  muscles 
of  the  thumb,  anastomosing  with  the  ramifications  of 
the  superficial  palmar  arch. 

(2.)  The  trunk  of  the  radial  artery  crosses  over 
the  lower  extremity  of  the  radius  to  the  back  of  the 
hand.  It  passes  under  the  extensors  of  the  thumb, 
over  the  os  scaphoides  and  the  junction  of  the  os  tra- 
pezium and  trapezoides,  and,  arriving  at  the  space 
betwixt  the  bases  of  the  metacarpal  bones  of  the 
thumb  and  fore-finger,  plunges  into  the  palm  of  the 
hand. 

The  branches  of  the  radial  artery,  in  its  course 
along  the  fore-arm,  are  the  following. 

(1.)  The  recurrent  artery  is  sent  off  from  the  radial 
immediately  after  it  leaves  the  ulnar  artery,  and  is 
distributed  over  the  anterior  part  of  the  outer  condyle, 


246 

where  it  anastomoses  with  branches  of  the  brachaal 
artery. 

(2.)  Small  arteries  to  the  muscles  of  the  fore-arm, 
and  to  the  radius. 

(3.)  A  branch  leaves  the  artery  immediately  after 
it  has  turned  over  the  edge  of  the  radius,  and,  ramify- 
ing on  the  back  of  the  hand,  is  named  Dorsalis  Carpi, 

(4.)  Small  vessels  are  sent  off  to  the  back  part  of 
the  thumb,  named  A.  Dorsales  Pollicis. 

Having  reached  the  palm  of  the  hand,  the  radial 
artery  divides  into  two  branches. 

(1.)  A.  Pollicis,  which  sends  two  or  three  arteries 
along  the  anterior  part  of  the  thumb,  and  also  often 
gives  off  a  twig,  the  A.  Radialis  Indicis,  which  passes 
along  the  outer  edge  of  the  fore-finger,  and  inosculates 
with  a  branch  of  the  ulnar  artery. 

(2.)  The  trunk  of  the  radial  artery  forms  the 
DEEP-SEATED  PALMAR  ARCH.  From  the  root  of  the 
thumb,  it  passes  across  the  metacarpal  bones  near 
their  bases,  and  terminates  at  the  metacarpal  bone  of 
the  little  finger,  inosculating  with  a  branch  of  the 
ulnar  artery.  This  arch  lies  deep,  close  to  the  bones. 
It  supplies  the  interosseous  muscles  and  deep-seated 
parts  of  the  palm,  and  some  of  its  branches  pass 
betwixt  the  metacarpal  bones  to  the  back  of  the 
hand. 

2.  ARTERIA  ULNARIS,  or  Cubitalis.  The  ulnar 
artery  is  the  largest  branch  of  the  brachial,  and  gene- 
rally gives  off  the  interosseous  artery.  It  takes  its 
course  deep  among  the  muscles  on  the  inside  of  the 
fore-arm.  It  is  seen  passing  under  the  pronator  teres, 
flexor  carpi  radialis,  palmaris  longus,  and  flexor  sub- 
limis  perforatus,  but  over  the  flexor  profundus  perfo- 
rans.  It  descends  in  the  connecting  cellular  membrane 
between  the  flexor  sublimis  and  profundus;  but  about 
the  middle  of  the  fore-arm,  it  emerges  from  these 
muscles,  and  appears  at  the  ulnar  edge  of  the  arm, 


GUIDE    TO    ANATOMY.  241 

betwixt  the  flexor  sublimis  and  flexor  carpi  ulnaris. 
It  passes  over  the  annular  ligament  of  the  wrist,  which 
binds  down  the  flexor  tendons  of  the  fingers,  but  is 
covered  by  the  fascia  which  ties  down  the  tendon  of 
the  flexor  carpi  ulnaris.  It  passes  under  the  palmar 
aponeurosis,  on  the  inside  of  the  os  pisiforme,  reaches 
the  base  of  the  metacarpal  bone  of  the  little  finger, 
and  begins  to  form  the  SUPERFICIAL  PALMAR  ARCH, 
This  arch  lies  above  the  tendons  of  the  flexor  sublimis 
perforatus,  immediately  beneath  the  palmar  aponeu- 
rosis. It  crosses  the  metacarpal  bones  betwixt  their 
bases  and  the  middle  of  their  bodies.  It  begins  at  the 
root  of  the  little  finger,  and  terminates  at  the  root  of 
the  thumb,  in  inosculations  with  the  branches  of  the 
radial  artery.  The  convex  side  of  the  arch  is  turned 
towards  the  fingers,  and  sends  off  five'branches. 

(1.)  A  branch  to  the  muscles  and  inner  edge  of  the 
little  finger. 

(2.)  Ramus  digitalis  primus,  or  the  first  digital  ar- 
tery, which  runs  along  the  space  betwixt  the  two  last 
metacarpal  bones,  and  bifurcates  into  two  branches, 
one  to  the  outer  side  of  the  little  finger,  and  the  other 
to  the  inner  side  of  the  ring  finger. 

(3.)  The  second  digital  artery,  which  bifurcates  in 
a  similar  manner,  and  supplies  the  outer  edge  of  the 
ring  finger,  and  the  inner  side  of  the  middle  finger. 

(4.)  The  third  digital  artery,  which  is  distributed 
to  the  outer  edge  of  the  middle  finger,  and  to  the  inner 
side  of  the  fore  finger. 

(5.)  The  ramus  pollicis  ulnaris  is  the  last  branch 
of  the  ulnar  artery,  and  is  sent  to  the  muscles  of  the 
thumb. 

From  the  concavity  of  the  arch  are  sent  off  the  in- 
terosseous  arteries  of  the  palm,  small  twigs  which 
supply  the  deep  seated  parts,  and  perforate  betwixt 
the  metacarpal  bones  to  the  back  of  the  hand. 


248  LONDON    DISSECTOR,  OR 

The  brandies  of  the  ulnar  artery,  in  its  course  along 
the  fore-arm  and  wrist,  are  the  following. 

(1.)  The  RECURRENT  ARTERIES  are  two  in  number. 
They  are  sent  off  from  the  ulnar  artery  immediately 
below  the  elbow,  sometimes  in  one  common  branch, 
which  subdivides.  The  anterior  recurrent  runs  over 
the  fore  part  of  the  inner  condyle;  the  posterior  re- 
current passes  over  the  back  part.  These  arteries 
inosculate  with  branches  of  the  brachial. 

(2.)  Twigs  to  the  muscles  of  the  fore-arm. 

(3).  A.  Dorsalis  Carpi  is  sent  off  from  the  ulnar 
artery  a  little  above  the  wrist  to  the  back  of  the  hand. 
Twigs  are  also  given  off  to  the  annular  ligament  and 
neighboring  parts. 

(4.)  A.  PALMARIS  PROFUNDA  is  sent  off'  from  the 
ulnar  artery,  where  it  descends  on  the  inside  of  the  os 
pisiforme.  It  passes  into  the  flesh  at  the  root  of  the 
little  finger,  and  inosculates  with  the  termination  of 
the  deep  seated  palmar  arch  of  the  radial  artery. 

3.  ARTERIA  INTEROSSEA  (or  Interossea  Communis.) 
This  artery  is  generally  sent  off  from  the  ulnar.  It 
immediately  divides  into  two  branches: 

(1.)  The  external  or  posterior  interosseous  artery 
is  the  smaller  branch.  It  passes  through  the  upper 
part  of  the  interosseous  ligament,  to  supply  the  mus- 
cles on  the  posterior  part  of  the  fore  arm.  It  sends 
off  the  A.  Recurrens  Interossea,  which  ramifies  on  the 
middle  of  the  back  part  of  the  elbow  joint. 

(2.)  The  internal  or  anterior  interosseous  artery 
descends  close  upon  the  middle  of  the  interosseous 
ligament,  between  the  flexor  longus  pollicis  and  flexor 
profundus  perforans,  giving  twigs  to  the  adjacent 
muscles.  Arriving  at  the  upper  edge  of  the  pronator 
quadratus,  it  perforates  betwixt  the  radius  and  ulna 
to  the  back  part  of  the  arm,  and  spreads  its  extreme 
branches  on  the  wrist  and  back  of  the  hand. 


GUIDE    TO    ANATOMY.  249 


VEINS. 

The  cutaneous  veins  have  been  already  described. 

The  brachial  artery  is  accompanied  by  two  veins, 
named  Venae  Comites,  or  Satellites.  These  receive 
branches  corresponding  to  the  ramifications  of  the 
artery. 

NERVES. 

In  the  dissection  of  the  axilla,  we  demonstrated  the 
great  axillary  plexus,  and  traced  its  first  two  branches, 
the  external  scapular  and  circumflex  nerves.  The 
distribution  of  the  five  remaining  branches  of  the 
plexus  must  now  be  described. 

(3.)  The  EXTERNAL  CUTANEOUS  NERVE  (Muscu- 
lo-cutaneus,  or  Perforans  Casserii)  is  the  third  branch 
of  the  axillary  plexus.  It  passes  through  the  belly  of 
the  coraco-brachialis  muscle.  After  its  passage,  it 
continues  its  course  obliquely  across  the  arm,  betwixt 
the  Biceps  flexor  cubiti  and  the  Brachialis  internus. 
It  gives  twigs  to  these  muscles,  and  appears  as  a  su- 
perficial nerve  on  the  edge  of  the  supinator  longus. 
It  runs  over  the  outer  condyle,  and  is  distributed  to 
the  integuments  on  the  outside  of  the  fore  arm,  and 
back  of  the  hand. 

(4.)  The  RADIAL  (or  Median)  NERVE  accompanies 
the  brachial  artery  to  the  bend  of  the  elbow,  and  is 
contained  in  the  same  sheath  as  the  artery.  In  its 
passage  down  the  arm,  it  lies  before  that  vessel,  but 
at  the  elbow  is  situated  on  its  inside.  It  gives  off  no 
branches  until  it  has  sunk  under  the  aponeurotic  ex- 
pansion of  the  biceps  flexor.  Here  it  distributes  many 
nerves  to  the  muscles  of  the  fore  arm,  to  the  pronator 
teres,  flexor  carpi  radialis,  the  flexors  of  the  thumb 
and  fingers,  and  the  pronator  quadratus.  The  trunk 
of  the  nerve  perforates  the  pronator  teres,  passes  be- 
twixt the  flexor  digitorum  sublimis  and  flexor  profun- 


250  LONDON    DISSECTOR,  OR 

dus,  and  continues  its  course  betwixt  these  muscles 
down  to  the  wrist.  Near  the  wrist  it  becomes  more 
superficial,  lying  amongst  the  tendons  of  the  flexors, 
and  before  it  descends  under  the  annular  ligament, 
sends  a  superficial  branch  to  the  integuments,  and  the 
short  muscles  of  the  thumb.  The  nerve  itself  passes 
with  the  flexor  tendons  of  the  fingers  under  the  annu- 
lar ligament  of  the  wrist,  emerges  from  these  tendons, 
and  appears  on  their  outside,  near  the  root  of  the 
thumb.  It  ramifies  superficially  in  the  hand,  sending  off 
four  branches.  The  first  branch  passes  to  the  thumb; 
the  second  to  the  side  of  the  fore  finger  next  the  thumb; 
the  third  divides  into  two  nerves,  of  which  one  passes 
to  the  inner  side  of  the  fore  finger;  the  fourth  also 
subdivides  into  two,  to  the  inside  of  the  middle  finger, 
and  outer  side  of  the  ring-finger.  These  nerves  pass 
before  the  flexor  tendons,  but  behind  the  superficial 
palmar  arterial  arch,  to  reach  the  fingers. 

(5.)  The  ULNAR  NERVE  descends  along  the  inside 
of  the  arm.  It  is  at  first  situated  immediately  under 
the  integuments,  but  below  the  middle  of  the  arm  is 
tied  down  by  the  intermuscular  ligament  which  passes 
to  the  inner  condyle  of  the  humerus.  The  nerve  be- 
comes here  more  deeply  seated;  it  runs  between  the 
inner  condyle  in  the  hollow  behind  it  and  the  olecra- 
non,  and  in  the  flesh  of  the  brachialis  externus  or  third 
head  of  the  triceps  extensor.  After  passing  the  con- 
dyle, it  continues  its  course  betwixt  the  two  heads  of 
the  flexor  carpi  ulnaris,  till  it  reaches  the  ulnar  artery. 
It  then  accompanies  the  ulnar  artery,  lying  on  its  in- 
side, and  running  along  the  fore  arm  between  the 
flexor  ulnaris  and  flexor  digitorum  sublimis.  It  sends 
twigs  to  the  neighboring  muscles,  and,  when  arrived 
near  the  wrist,  divides  into  two  branches.  1 .  The 
Smaller  Branch,  called  Ramus  Posticus,  passes  under 
the  tendon  of  the  flexor  carpi  ulnaris,  and  over  the 
lower  end  of  the  ulna,  to  be  distributed  to  the  back 


GUIDE   TO   ANATOMY.  251 

of  the  hand,  and  of  the  little  and  ring-fingers.  2..  The 
continued  trunk  of  the  nerve  passes,  on  the  inside  of 
the  ulnar  artery,  over  the  annular  ligament  of  the 
wrist.  It  passes  under  the  palmar  aponeurosis,  and 
divides  into  three  principal  branches.  The  first  sup- 
plies the  integuments  and  muscles  on  the  ulnar  edge 
of  the  hand,  and  the  inner  side  of  the  little  finger. 
The  second  is  distributed  to  the  outer  side  of  the  little 
finger,  and  inner  side  of  the  ring-finger.  The  third 
branch  passes  deep  under  the  long  tendons,  accompa- 
nies the  deep  seated  palmar  arch,  and  terminates  in 
the  short  muscles  of  the  thumb  and  fore  finger,  com- 
municating with  the  radial  nerve. 

(6.)  The  MUSCULAR  or  SPIRAL  NERVE  (RADIAL 
of  some  anatomists)  passes  from  the  axilla  behind  the 
os  humeri,  making  a  spiral  turn  round  the  bone  to 
reach  the  outside  of  the  arm.  It  first  descends  be- 
tween the  brachialis  externus  and  short  head  of  the 
biceps  extensor  cubiti,  accompanying  the  arteria  pro- 
funda  humeri  superior,  and  passing  deep  into  the  flesh 
of  the  arm.  Before  it  makes  this  turn,,  it  gives  branches 
to  the  muscles,  also  a  cutaneous  branch,  which  de- 
scends on  the  inside  of  the  arm.  From  the  back  part 
of  the  arm  the  great  trunk  of  the  nerve  is  reflected 
spirally  forwards.  It  is  seen  emerging  betwixt  the 
supinator  longus  and  brachialis  internus,  seated  deep 
and  close  to  the  bone.  It  descends  betwixt  these 
muscles,  keeping  close  to  the  edge  of  the  supinator 
longus.  Immediately  after  passing  the  fold  of  the 
arm,  it  sends  off  a  nerve,  which  descends,  superficial, 
upon  the  radial  edge  of  the  fore  arm,  as  far  as  the 
wrist;  and,  at  this  point,  the  trunk  of  the  muscular 
nerve  divides  itself  into  two  branches.  The  first,  a 
large  branch,  perforates  the  supinator  brevis,  and 
supplies  the  extensor  muscles  of  the  hand  and  fingers. 
The  second  branch  accompanies  the  supinator  longus 
down  the  fore  arm,  and  near  the  wrist  turns  under  the 


LONDON   DISSECTOR.    OR 

tendon  of  that  muscle,  over  the  edge  of  the  radius.  It 
then  divides  into  several  branches,  which  ramify  on 
the  back  of  the  wrist,  thumb,  and  fore  finger. 

(7.)  The  INTERNAL  CUTANEOUS  NERVE  descends 
superficial,  along  the  inside  of  the  arm  and  fore  arm. 
It  was  described  among  the  cutaneous  nerves  of  the 
arm. 


THE  METHOD   OF   INJECT  I  NGTHE 
ARTERIES. 

FOR  the  student,  who  desires  to  obtain  a  general 
view  of  the  arteries,  it  will  be  sufficient  to  inject  them 
from  the  arch  of  the  aorta.  For  this  purpose  an 
incision  is  to  be  made  through  the  integuments  along 
the  centre  of  the  sternum  throughout  its  whole  length; 
and  the  sternum  divided  longitudinally  with  a  saw: 
then  lay  open  the  thorax  by  bending  back  the  two 
portions  of  the  sternum.  An  incision  is  then  to  be 
made  into  the  pericardium,  and  a  small  opening  in  the 
ascending  arch  of  the  aorta;  into  which  a  pipe  is  to  be 
inserted  and  well  secured. 

For  ordinary  purposes,  the  injecting  material  may 
consist  of  a  strong  heated  solution  of  glue  and  colour- 
ing matter. 

When  any  particular  part  of  the  body  alone  is  to  be 
injected,  it  is  necessary  to  introduce  the  pipe  into  the 
artery  which  supplies  that  particular  member:  thus, 
if  the  head  is  to  be  injected,  a  pipe  is  to  be  introduced 
into  each  common  carotid,  or,  wrhat  is  preferable,  one 
pipe  with  a  bifurcation,  and  the  vertebral  arteries  are 
to  be  secured  with  a  ligature.  If  an  arm,  insert  the 
pipe  into  the  axillary  artery;  and  for  the  lower  extrem- 
ity, fix  the  pipe  in  the  common  iliac  artery  according 
to  the  side  to  be  injected. 


GUIDE  TO  ANATOMY.  253 

METHOD  OF  INJECTING  THE  HEART  AND  GREAT 

VESSELS.* 

If  we  wish  to  inject  the  heart  while  it  is  in  its 
natural  situation,  we  must  sacrifice  almost  all  the  parts 
of  the  chest  to  it;  for  it  is  a  preparation  so  difficult  to 
make,  and  so  expensive,  that  when  we  undertake  it, 
we  must  not  hesitate  to  destroy  the  other  parts.  The 
chest,  for  this  purpose,  is  to  be  opened  by  cutting 
through  the  sternum  in  its  length,  and  by  bending  back 
the  lateral  portions.  The  abdomen  must  also  be 
opened.  The  viscera  are  to  be  pulled  down,  so  that 
a  large  pipe  may  be  put  into  the  aorta,  where  it  lies 
between  the  crura  of  the  diaphragm.  Another  pipe 
is  to  be  put  into  the  vena  cava  ascendens,  below  the 
liver. 

We  must  then  make  a  dissection  on  each  side  of 
the  neck,  so  as  to  expose  the  internal  jugular  veins, 
into  each  of  which,  a  pipe  should  be  put.  The  caro- 
tid and  vertebral  arteries  are  to  be  tied;  so  are  the 
subclavian:  or  perhaps  it  will  be  better  to  put  tight 
ligatures  on  the  arms,  just  below  the  insertion  of  the 
pectoralis  major. 

Previous  to  the  injection  of  the  veins,  a  quantity  of 
warm  water  should  be  thrown  into  them,  so  that  it  may 
pass  into  the  several  cavities  of  the  heart.  The  water  is 
then  to  be  pressed  out  along  with  the  coagula  which 
are  generally  found  in  the  cavities  of  the  heart.  It  is 
principally  upon  this^being  carefully  done,  that  a  good 
injection  of  the  heart  depends. 

When  the  parts  are  thoroughly  heated,  the  red 
injection  should  be  thrown  into  the  ascending  aorta. 
An  assistant  must  now  be  ready  to  knead  the  injection 
through  the  valves  of  the  aorta;  (but,  if  possible,  a 
probe  should  have  been  passed  from  the  carotid, 

*  Shaw's  Manual. 

22 


254  LONDON    DISSECTOR,  OR 

before  it  was  tied,  to  break  down  these  valves;)  when 
the  injection  once  passes  the  valves,  it  will  quickly 
distend  the  left  ventricle,  which  must  be  supported  by 
the  assistant, — the  pericardium  having  been  previously 
opened.  By  a  little  pressure,  the  wax  will  pass  into 
the  left  auricle,  and,  from  it,  into  the  pulmonary  veins. 
It  will  be  well  to  make  a  small  puncture,  with  a  lan- 
cet, in  the  apex  of  the  ventricle,  to  allow  the  escape 
of  any  water  or  blood  which  may  be  still  in  this  side 
of  the  heart. 

The  right  side  of  the  heart  may  be  filled  with  blue 
or  yellow  injection  from  the  pipes  which  have  been 
put  into  the  several  veins.  It  will  be  necessary  to 
make  a  puncture  in  the  apex  of  the  auricle,  to  permit 
the  exit  of  a  certain  quantity  of  water  which  will  be 
left  in  the  heart,  even  though  much  care  has  been 
taken  to  squeeze  it  all  out  previous  to  the  injection. 

Perhaps  the  vena  azygos  may  be  filled,  with  the 
other  veins;  but  if  it  be  not,  we  must  put  a  pipe  into 
it,  and  inject  it  separately. 

The  thoracic  duct  may  also  be  injected.  If  sought 
for  in  the  abdomen,  it  will  be  discovered  at  the  root 
of  the  mesenteric  vessels,  or  between  the  right  crus 
of  the  diaphragm  and  the  aorta.  It  may  be  traced  up 
under  the  diaphragm,  along  with  the  aorta,  and  upon 
its  right  side,  close  to  the  spine.  As  it  generally  lies 
collapsed  and  undistinguishable,  it  may  be  raised  by 
blowing  into  some  of  the  glands  upon  the  root  of  the 
mesentery,  or  into  those  upon  the  course  of  the  exter- 
nal iliac  vessels,  or  even  into  those  below  Poupart's 
ligament  in  the  groin.  It  must  be  injected  with  a 
different  color  from  the  veins,  that  it  may  not  be  con- 
founded, in  the  thorax  and  at  the  root  of  the  neck,  with 
their  branches. 

When  the  heart  only  is  to  be  injected,  we  should 
cut  through  the  vessels  going  to  the  upper  parts  of  the 
body,  as  they  are  emerging  from  the  thorax,  and 
remove  the  heart  and  lungs,  by  tearing  them,  along 


GUIDE   TO    ANATOMY.  255 

with  the  trachea  and  oesophagus,  from  the  spine, — 
making  first  an  incision  along  the  spine,  to  free  the 
intercostal  arteries.  We  may  then  cut  through  the 
aorta  and  vena  cava,  below  the  diaphragm: — a  part  of 
the  liver  should  be  left  attached  to  the  vessels.  It  is 
necessary  to  remove  the  heart  in  this  manner,  that 
there  may  be  no  danger  of  cutting  any  of  the  great 
vessels. 

We  should  press  out  as  much  blood  as  possible  from 
the  vessels,  and  then  put  a  pipe  into  one  of  the  pul- 
monary veins,  and  another  into  the  vena  cava  superior. 
Having  injected  warm  water  by  these  tubes,  to  clear 
the  heart  of  the  masses  of  coagulated  blood  which  are 
generally  found  in  it  after  death,  we  must  tie  the  lungs 
at  their  roots,  and  the  vena  cava  inferior,  and  all  the 
divided  arteries,  except  the  aorta,  in  which  a  pipe 
must  be  put.  If  we  throw  red  injection  into  the  pul- 
monary vein,  it  will  fill  the  left  auricle,  left  ventricle, 
aorta,  and  coronary  vessels;  but  during  this  part  of  the 
injection,  an  assistant  ought  to  hold  and  compress  the 
aorta  immediately  after  its  giving  off  the  coronary 
arteries,  so  as  to  press  the  injection  on  in  them;  but 
as  by  this,  the  injection  will  be  prevented  from  enter- 
ing the  aorta,  it  must  be  filled  from  the  pipe  which 
was  inserted  into  it.  The  injection  escaping  by  the 
intercostal  arteries,  may  be  stopped  by  an  assistant 
throwing  cold  water  on  the  wax  as  it  flows  from  the 
vessels.  The  yellow  injection  thrown  in  by  the  vena 
cava  superior,  will  fill  the  right  auricle,  ventricle,  and 
pulmonary  artery.  The  dissection  required  is  simply 
the  removing  of  the  soft  parts  from  the  injected  ves- 
sels. 


256 


THE   LYMPHATIC,  OR  ABSORBENT 
SYSTEM.* 

THE  lymphatic  system  consists  of  an  elaborate  set 
of  vessels,  and  of  a  number  of  glands  distributed  in 
various  parts  in  the  course  of  these  vessels. 

The  lymphatic  vessels  are  tubes  whose  coats  are  per- 
fectly pellucid,  having-  a  remarkable  power  of  contrac- 
tion. They  are  called  LYMPHATICS,  or  DUCTUS  Aauosi, 
from  their  transmitting  a  fluid  colorless  as  water. 
When  distended  with  their  fluids,  they  show  that  they 
possess  a  character  distinct  from  other  vessels,  being 
irregularly  distended,  knotty,  presenting  sometimes 
the  appearance  of  a  chain  of  beads,  or  little  irregular 
vesicles  connected  together.  Everywhere  throughout 
the  human  body  and  the  viscera,  between  the  extreme 
branches  of  the  absorbent  system  and  the  trunk,  gland- 
ular bodies  are  interposed.  These  glands,  though 
differing  m  form,  are  generally  of  an  oval  shape,  vary- 
ing in  size  from  the  twentieth  part  of  an  inch  to  an 
inch  in  diameter.  Sometimes  they  are  separate, 
sometimes  accumulated  and  clustered  together.  The 
color  of  these  bodies  is  various  in  the  several  parts 
of  the  body,  in  the  outer  parts,  as  in  the  thigh,  axilla, 
&c.,  they  are  redder  and  stronger;  but  less  so  within 
the  abdomen  and  thorax.  In  children  the  lacteal  and 
lymphatic  glands  are  exceedingly  numerous,  but  they 
shrink  with  advancing  old  age. 

The  function  of  these  glands  seems  to  be  to  check, 
control  and  measure  the  flow  of  the  absorbed  fluids 
into  the  mass  of  the  blood,  and  perhaps  also,  to  pro- 
duce some  modification  in  the  fluid  which  is  conveyed 
to  them.  According  to  Bell,  the  lymphatics  form  a 
system  of  absorbents  which  take  up  the  fluids  extra- 
vasated,  or  secreted  on  the  surfaces  of  membranes 
and  cavities.  Thus  they  arise  from  the  pores  of  the 

*  Bell's  Anatomy. 


GUIDE   TO    ANATOMY.  257 

skin;  from  the  surface  of  the  cavities  and  viscera, 
which  are  covered  by  the  pleura  and  peritoneum;  from 
the  cells  of  the  interstitial  and  adipose  membrane;  from 
all  the  ducts  and  cavities  of  the  body.  But  whether 
they  are  the  only  system  of  absorbents;  whether  they 
carry  away  all  the  parts  of  the  system,  fluids  and 
solids;  whether  they  absorb  the  muscles,  membranes, 
bones,  tendons,  &c.,  of  which  the  solid  body  consists, 
as  well  as  the  secreted  fluids,  are  questions  which  we 
must  leave  to  the  examination  of  physiologists. 


OF  THE  COURSE  OF  THE  LYM- 
PHATICS. 

THE  lymphatics,  in  their  course  and  relation  to  the 
fascia  and  muscles  of  the  extremities,  bear  a  great 
analogy  to  the  veins;  for  there  are  two  sets  or  grand 
divisions, — the  DEEP  LYMPHATICS  which  accompany 
the  arteries  in  their  branchings  among  the  muscles^ 
and  the  SUPERFICIAL  set  which  run  a  course  external 
to  the  fascia. 

OF  THE  FOOT,  LEG  AND  THIGH. — Even  in  the  toes 
the  same  distinction  of  the  origins  of  the  lymphatics 
may  be  observed,  as  in  the  limb.  For  while  a  plexus 
covers  the  toes  superficially,  and  runs  up  upon  the 
foot  with  the  veins,  deeper  branches  accompany  the 
arteries  on  the  side  of  the  toes. 

From  the  toes,  dorsum,  and  edges  of  the  foot,  the 
lymphatics  ascend  along  the  leg  in  four  classes.  1 . 
One  takes  a  course  from  the  root  of  the  great  toe  and 
inside  of  the  foot,  over  the  tendons  of  the  great  toe 
and  tibialis  anticus  tendon.  It  then  passes  on  the 
inside  of  the  tendon  of  the  tibialis  anticus  muscle, 
and  before  the  head  of  the  tibia,  following  the  prin- 
22* 


258  LONDON    DISSECTOR,  OR 

cipal  branch  of  the  great  saphena  vein;  and  then 
continues  its  course,  in  company  with  the  saphena, 
to  the  inside  of  the  knee.  2.  There  is  at  the  same 
time  a  considerable  number  of  lymphatics,  taking 
their  origin  from  nearly  the  same  place,  viz.  the 
inside  of  the  foot,  and  before  the  inner  ankle;  but  they 
take  a  different  course  on  the  leg  from  the  last  class; 
for  they  pass  behind  the  lower  head  of  the  tibia:  they 
attach  themselves  to  some  branch  of  the  saphena  vein, 
and  join  the  former  set  of  vessels  on  the  inside  of  the 
knee.  From  this  they  ascend  superficially  above  the 
fascia  to  the  glands  of  the  groin.  3.  From  the  out- 
side of  the  foot  there  ascend  several  lymphatics;  a 
division  of  which  passes  before  the  outer  ankle  and 
across  the  tibia  to  join  the  lymphatics,  parasites  of 
the  great  saphena  vein,  and  here  they  sometimes  form 
plexuses  and  contortions;  others  turn  in  behind  the 
outer  ankle,  and  join  the  branches  accompanying  the 
lesser  saphena  vein. 

The  lymphatics  which  turn  round  behind  the  outer 
ankle  pass  on  the  outside  of  the  tendo  Achillis;  and 
accompanying  the  lesser  saphena  vein,  sink  into  the 
popliteal  hollow.  Here  they  unite  with  the  lymphatics 
which  have  accompanied  the  several  arteries  of  the 
leg  and  foot,  and  particularly  the  posterior  tibial 
artery. 

The  deep  lymphatics  accompany  the  arteries,  as 
we  have  said;  and  to  inject  them  we  should  look  for 
a  very  large  vessel  which  is  coming  out  from  under 
the  plantar  aponeurosis  to  rise  behind  the  inner  ankle, 

POPLITEAL  GLANDS. — The  glands  of  the  ham-string 
cavity  are  generally  three  in  number,  and  very  small. 
They  receive  some  of  the  lymphatics  which  pass  with 
the  posterior  tibial  artery  and  with  the  lesser  saphena. 

From  the  popliteal  glands  there  ascend  two  large 
lymphatics,  which  accompany  the  popliteal  artery 
and  venae  comites,  and  ascend  with  the  latter  through 
the  adductor  magnus  to  the  fore  part  of  the  thigh, 


GUIDE    TO    ANATOMY.  259 

They  run  irregularly,  or  form  a  kind  of  net-work 
round  the  great  vessels.  On  the  fore  part  of  the  thigh, 
and  still  deep,  they  enter  the  lower  and  deep  inguinal 
glands. 

Sometimes  these  deep  lymphatics,  instead  of  being 
accumulated  into  larger  trunks,  divide  into  many 
branches,  and  only  unite  in  the  glands  of  the  groin. 

INGUINAL  GLANDS. — The  inguinal  glands  are  in 
number  from  tive  to  ten;  they  lie  involved  in  cellular 
membrane  on  the  outside  of  the  femoral  ligament. 
Some  of  them  are  superficial  and  moveable  under  the 
integuments;  some  involved  in  the  laminae  of  the  fascia, 
which  descend  from  the  abdominal  muscles;  some  are 
close  on  the  femoral  artery  and  vein,  and  under  the 
fascia.  Nearer  to  the  pubes  may  be  observed  a 
division  of  these  glands  which  belong  to  the  lymphatics 
of  the  penis,  perineum,  &c. 

LYMPHATICS  OF  THE  PARTS  OF  GENERATION  IN 
BOTH  SEXES. — From  the  penis  there  run  backwards 
two  sets  of  lymphatics;  superficial  ones,  which  take 
a  course  to  the  groin;  and  deeper  ones,  which  take  a 
course  along  the  arteries  of  the  penis  into  the  pelvis, 
or  under  the  arch  of  the  pubis.  The  superficial  lym- 
phatics are  the  cutaneous  vessels,  and  take  their  origin 
from  the  prepuce. 

In  the  external  parts  of  the  female  there  are  also 
two  sets  of  lymphatics.  Those  near  the  clitoris  pass 
up  in  a  direction  to  the  ring;  and  those  from  the  lower 
part  of  the  vulva  and  perineum  to  the  glands  of  the 
groin. 

LYMPHATICS  AND  GLANDS  WITHIN  THE  LIGAMENT 
OF  THE  THIGH. — The  vasa  efferentia  of  the  inguinal 
glands  are  in  number  from  two  to  six.  The  deep 
lymphatics  which  accompany  the  femoral  vein  and 
artery,  lying  under  the  cellular  membrane,  pass  under 
the  ligament,  and  soon  form  a  large  net  work  of  ves- 
sels accompanying  the  iliac  vessels;  and  here  they 


260  LONDON    DISSECTOR,  OR 

are  joined  by  the  branches  of  lymphatics  from  the 
superficial  glands;  sometimes  the  trunks,  accompany- 
ing the  great  vessels  of  the  thigh,  pass  into  a  gland 
immediately  within  the  ligament;  sometimes  one  or 
two  of  them  only  enter  into  the  glands  high  in  the  loins; 
nay,  sometimes  a  large  vessel  passes  on  directly  to 
the  thoracic  duct. 

From  six  to  eight  or  ten  glands  are  seated  in  the 
tract  of  the  external  iliac  vessels,  under  the  name  of 
EXTERNAL  ILIAC  GLANDS.  And  upon  the  inside  of 
the  brim  of  the  pelvis,  and  on  the  hypogastric  vessels, 
the  glands  are  called  the  INTERNAL  ILIAC  GLANDS. 
On  the  psoas  muscle,  and  on  the  loins,  it  is  impossible 
to  trace  the  vessels  as  single  trunks;  we  may  observe 
that  one  net- work  of  vessels  ascends  upon  each  psoas 
muscle  from  the  thigh;  and  it  is  there  joined  by  the 
lymphatics  of  the  pelvis.  These  vessels  are  in  a 
manner  united  to  those  which  cover  the  prominence 
of  the  sacrum,  and  pass  under  the  bifurcation  of  the 
aorta.  These  two  GREAT  LUMBAR  plexuses  of  the 
lymphatics  continuing  their  ascent,  many  of  the  vessels 
enter  into  the  lumbar  glands;  and  on  the  loins  they  are 
joined  by  the  absorbents  of  the  testicle.  By  the  union 
of  the  lymphatics  ascending  from  the  right  and  left 
side,  with  several  large  trunks  of  the  lacteals  from  the 
root  of  the  mesentery,  the  thoracic  duct  is  formed  on 
the  third  and  fourth  vertebrae  of  the  loins. 

OF    THE     LYMPHATICS    OF    THE    ARM. 

In  the  arm,  as  in  the  leg  and  thigh,  there  are  two 
sets  of  lymphatics: — the  superficial  and  the  deep- 
seated.  The  first  of  these  accompany  the  cutaneous 
veins,  the  latter  the  deep  arteries. 

As  in  general  there  are  too  great  veins  on  the  fore- 
arm, the  basilic  and  cephalic  veins;  but  particularly 
as  the  veins  which  gather  into  the  basilic  trunk,  on 
the  inner  and  lower  edge  of  the  fore-arm,  are  the 


GUIDE    TO    ANATOMY.  261 

larger  and  more  numerous  class;  so  it  is  found  that 
the  course  of  the  more  numerous  class  of  lymphatics 
is  on  the  lower  and  inner  side  of  the  fore-arm,  and 
that  they  accumulate  about  the  basilic  vein.  These 
are  derived  from  the  palm  of  the  hand,  and  from  the 
ulnar  edge  of  the  hand.  This  set  sometimes  passes 
into  glands,  seated  on  the  brachial  artery,  near  the 
inner  condyle  of  the  humerus. 

The  absorbents  which  accompany  the  cephalic 
vein  arise  from  the  side  of  the  thumb  and  fore- 
finger upon  the  back  of  the  hand;  they  run  on  the 
radial  edge  of  the  arm,  with  the  veins  which  ascend 
to  form  the  cephalic  vein.  From  the  bend  of  the 
arm,  these  vessels  take  a  course  on  the  outer  edge  of 
the  biceps,  and  then  get  between  the  inner  edge  of 
the  deltoid,  and  outer  edge  of  the  pectoral  muscles; 
they  then  pass  under  the  clavicle,  and  descend  into 
the  axillary  glands.  This  set  of  absorbents  receives 
the  branches  from  the  outside  of  the  arm  in  their 
whole  course. 

There  are  absorbents  arising  from  the  back  of  the 
hand,  next  the  little  finger,,  which,  following  some  of 
the  branches  of  the  basilic  vein,  (a  larger  branch  of 
which  is  called  the  ulnaris  externa)  turn  round  the 
ulnar  edge  of  the  arm,  are  inserted  into  a  gland,  very 
commonly  found  before  and  a  little  above  the  inner 
condyle  of  the  humerus.  From  this  gland  a  large 
lymphatic  passes  upwards,  and  attaching  itself  to  the 
brachial  artery,  splits  and  plays  around  it. 

The  deep-seated  lymphatics  of  the  arm  accompany 
the  arteries  in  the  same  manner  as  the  venae  comites 
do;  in  general,  two  with  each  artery.  They  all  ter- 
minate in  the  glands  of  the  axilla,  and  can  require  no 
particular  description.  The  lymphatics,  from  the 
muscles  and  integuments  on  the  back  of  the  shoulder, 
also  turn  round  and  enter  into  the  glands  of  the  axilla. 

The  GLANDS  or  THE  ARM  are  small,  and  irregularly 


262  LONDON    DISSECTOR,    OR 

placed  in  the  course  of  the  humeral  artery,  from  the 
condyle  to  the  axilla.  They  are  from  three  to  six 
in  number. 

The  GLANDS  OF  THE  AXILLA  are  large  and  nume- 
rous; they  receive  the  lymphatics  from  the  arm,  breast, 
and  shoulder;  they  lie  in  the  deep  cavity  of  the  axilla, 
formed  by  the  tendons  of  the  pectoralis  major,  and 
latissimus  dorsi  muscles.  They  are  embedded  in  a 
loose  cellular  membrane,  which,  while  it  surrounds 
and  supports  the  vessels  of  the  axilla  in  the  motions 
of  the  joint,  gives  them  strength  from  its  elasticity. 
These  glands  do  not  all  surround  the  axillary  artery; 
but  a  lower  cluster  is  attached  to  the  branches  of  the 
subscapular  artery,  going  forward  on  the  side  of  the 
chest,  and  to  the  thoracic  arteries. 

LYMPHATICS  OF  THE  HEAD  AND  NECK. 

Of  the  absorbents  of  the  brain,  little  is  known  pre- 
cisely; but  none  can  deny  the  probability,  that  the 
arteries,  veins,  and  lymphatics  bear  the  same  relations 
in  the  brain  as  in  the  other  parts  of  the  system.  Lym- 
phatic glands  are  observed  in  the  course  of  the  internal 
jugular  vein,  and  even  in  the  foramen  caroticum,  which 
are  understood  to  belong  to  the  lymphatics  of  the 
brain.  The  lymphatics  of  the  head  are  to  be  observed 
in  the  course  of  the  temporal  and  occipital  arteries;  the 
latter  class  terminate  in  glands,  seated  behind  the  mas- 
toid  process  of  the  temporal  bone.  The  lymphatics  of 
the  face  have  been  observed  to  be  very  numerous,  ac- 
companying the  facial  and  temporal  arteries.  But  those 
from  the  internal  parts  of  the  face  and  nose  accompany 
the  internal  maxillary  artery,  and  fall  into  the  glands 
under  the  parotid,  or  in  the  course  of  that  artery. 
The  lymphatics  from  the  gums  and  jaws  accompany 
the  internal  maxillary  artery,  and  emerge  under  the 
angle  of  the  jaw;  and  some  of  them  joining  the  exter- 
nal jugular  vein,  pass  through  glands  near  the  top  of 


GUIDE    TO    ANATOMY.  263 

the  shoulder.  The  lymphatic  vessels  from  the  tongue 
and  parts  ahout  the  os  hyoides,  take  also  the  same 
course. 

There  are  in  general  several  small  lymphatic  glands, 
on  the  side  of  the  face,  on  the  buccinator  muscle, 
immersed  in  the  surface  of  the  parotid  gland,  and 
under  the  zygomatic  process.  There  are  also  glands 
to  be  carefully  noted,  which  lie  under  the  tip  of  the 
parotid  gland,  where  it  extends  behind  the  angle  of 
the  jaw,  and  also  lying  under  the  base  of  the  jaw-bone, 
close  to  the  sub-maxillary  gland,  and  on  the  course 
of  the  facial  artery. 

The  GLANDS  and  ABSORBENTS  of  the  neck  are  very 
numerous,  and  the  latter  form  an  intricate  and  beauti- 
ful plexus,  several  branches  of  which  are  to  be  ob- 
served accompanying  the  external  and  internal  jugular 
veins.  Some  of  the  glands  lie  immediately  under  the 
skin,  and  in  the  cellular  membrane,  on  the  outer  edge 
of  the  platisma  myoides;  many  under  that  muscle, 
and  in  the  course  of  the  external  jugular  vein.  But 
there  are  many  seated  deep,  for  the  greater  number 
accompany  the  internal  carotid  artery,  and  internal 
jugular  vein,  or  their  branches. 

The  lymphatics  of  the  THYROID  GLAND  have  been 
raised  by  Mr.  Cruickshanks,  by  plunging  a  lancet  at 
random  into  the  substance  of  the  gland,  and  blowing 
into  it,  or  throwing  quicksilver  into  its  cellular  mem- 
brane. The  trunks  of  these  lymphatics  join  the  tho- 
racic duct  on  the  left  side;  and  on  the  right  side,  they 
unite  with  the  right  trunk  of  the  absorbing  system, 
just  as  it  is  about  to  enter  the  jugular  vein. 

OF  THE    TRUNKS  OF    THE   ABSORBENT   SYSTEM. 

The  larger  and  proper  trunk  of  the  lymphatic  sys- 
tem is  generally  called  the  THORACIC  DUCT,  because 
it  was  first  observed  by  Pecquet*  to  be  a  vessel  which 

*  In  the  year  1651. 


264  LONDON   DISSECTOR,    OR 

conveyed  the  chyle  through  the  diaphragm,  and  which 
took  its  course  through  the  whole  length  of  the  tho- 
rax, to  discharge  its  fluids  into  the  veins  near  the 
heart.  The  origin  of  this  great  trunk,  called  the 
thoracic  duct,  is  the  union  of  the  vessels  which  ascend 
by  the  side  of  the  common  iliac  arteries  and  veins, 
and  are  derived  from  the  pelvis  and  lower  extremi- 
ties. Upon  the  third  and  fourth  lumbar  vertebras, 
and  under  the  aorta,  this  trunk  is  frequently  joined  by 
a  large  trunk  of  the  lacteals,  and  then  ascending,  it 
receives  the  greater  number,  or  the  larger  trunks  of 
the  lacteals.  On  the  vertebras  of  the  loins,  the  tho- 
racic duct  is  by  no  means  regular,  either  in  its  course, 
or  size,  or  shape;  often  it  contracts,  and  again  irregu- 
larly dilates,  as  it  seems  to  emerge  from  under  the 
aorta.  On  the  uppermost  vertebra  of  the  loins,  the 
thoracic  duct  lies  between  the  right  crus  of  the  dia- 
phragm and  the  aorta.  From  this  point  it  runs  up  on 
the  face  of  the  dorsal  vertebrae,  and  between  the  vena 
azygos  and  the  aorta.  On  the  fourth  dorsal  vertebra 
it  passes  under  the  aorta  to  gain  the  left  side  of  it. 
Here  it  is  considerably  enlarged,  from  the  contracted 
state  which  it  assumes  in  the  thorax.  Sometimes  it 
splits,  and  again  unites  on  the  vertebras  of  the  back. 
Still  ascending,  it  continues  to  incline  to  the  left  side, 
and  may  be  found  by  the  side  of  the  oesophagus. 

The  thoracic  duct  now  emerges  from  the  thorax, 
and  lies  deep  in  the  lower  part  of  the  neck,  behind 
the  lower  thyroid  artery,  and  on  the  longus  colli 
muscle. 

It  rises  above  the  level  of  the  subclavian  vein  of 
the  left  side,  and  here  it  receives  the  absorbents  of 
the  head  and  neck,  (of  the  left  side,)  and  descends 
again  with  a  curve,  and  terminates  in  the  angle  formed 
by  the  union  of  the  subclavian  vein  and  jugular  vein 
of  the  left  side. 

Sometimes  there  are  two  thoracic  ducts;  but  this 


GUIDE   TO   ANATOMY.  265 

Is  very  rare.  Sometimes  the  duct  splits  near  its  ter- 
mination, and  the  two  branches  enter  the  veins 
separately;  but,  in  general,  when  it  splits  in  this  man- 
ner, it  again  unites  before  it  terminates  in  the  vein. 
There  is  constantly  a  trunk  in  the  anterior  medias- 
tinum under  the  sternum,  almost  as  large  as  the  tho- 
racic duct  itself,  which  is  sometimes  inserted  into  the 
termination  of  the  thoracic  duct;  sometimes  into  the 
trunk  of  the  absorbents  of  the  right  side,  to  be  imme- 
diately described. 

THE    TRUNK    OF    THE    ABSORBENTS    OF    THE    RIGHT 
SIDE. 

The  absorbents,  from  the  right  side  of  the  head 
and  neck,  and  from  the  right  arm,  do  not  run  across 
the  neck,  to  unite  with  the  great  trunk  of  the  system; 
they  have  an  opportunity  of  dropping  their  contents 
into  the  angle  between  the  right  subclavian  and  the 
right  jugular  vein.  These  vessels  then  uniting,  form 
a  trunk  which  is  little  more  than  an  inch,  nay,  some- 
times not  a  quarter  of  an  inch  in  length,  but  which 
has  nearly  as  great  a  diameter  as  the  proper  trunk  of 
the  left  side. 

The  trunk  of  the  right  side  lies  upon  the  subcla- 
vian vein,  and  receives  a  very  considerable  number 
of  lymphatic  vessels:  not  only  does  it  receive  the 
lymphatics,  from  the  right  side  of  the  head,  thyroid 
gland,  neck,  &c.,  and  the  lymphatics  of  the  arm;  but 
it  receives  also  those  from  the  right  side  of  the  thorax 
and  diaphragm,  from  the  lungs  of  this  side,  and  from 
the  parts  supplied  by  the  mammary  artery.  Both  in 
this  and  in  the  great  trunk  there  are  many  valves. 

23 


266  LONDON    DISSECTOR,  OR 

OF     THE     LACTEALS     AND      LYMPHATICS     OF     THE 
INTESTINAL    CANAL. 

The  lymphatics  situated  on  the  alimentary  canal 
are  named  lacteals,*  and  both  these  and  the  other  lym- 
phatics are  also  termed  absorbents. 

The  lacteals  are  those  lymphatics  or  absorbents 
situated  on  the  intestinal  canal,  being  named  so  from 
the  commencement  of  the  duodenum  to  the  termina- 
tion of  the  rectum.  But  there  are  other  absorbents 
which  carry  the  lymph  from  the  tissue  of  the  intestines, 
and  which  are  simply  named  lymphatics,  although 
they  take  the  same  course.  They  are  subdivided 
into  lactea  primi  generis,  and  lactea  secundi  generis. 

The  lactea  primi  generis  are  those  which  extend 
from  the  intestines  to  the  lymphatic  glands  situated 
in  the  folds  of  the  mesentery;  and  the  lactea  secundi 
generis  are  those  which  extend  from  the  lymphatic 
glands  to  the  thoracic  duct. 

Mr.  Cruickshanks  has  remarked  a  deep  and  a  super- 
ficial set  of  lacteals  on  the  intestines;  but  for  this 
division  there  seems  no  necessity.  Deep  in  the  coats 
the  lacteals  seem  to  accompany  the  blood  vessels; 
but  when  they  get  more  superficial,  they  take  a  course 
longitudinally  on  the  canal,  and  after  running  a  little 
way,  they  take  a  sudden  turn  towards  the  mesentery. 

As  the  greater  frequency  of  the  valvulae  conajventes 
in  the  jejunum,  greatly  increases  the  extent  of  the  inner 
surface  of  that  gut,  and  consequently  gives  a  greater 
extent  of  origin  to  the  lacteals;  and,  as  here,  the  chyle 
must  be  in  the  greater  quantity,  so  the  lacteals  of 
this  portion  of  the  gut,  are  larger  and  more  nume- 
rous than  in  any  other  part  of  the  canal. 

The  lacteals  do  not  attach  themselves  to  the  vessels 

*   Vasa  chylifera. 


GUIDE    TO    ANATOMY.  267 

of  the  mesentery,  but  take  a  more  superficial  course. 
Before  they  enter  the  mesenteric  glands,  they  have 
been  called  lacteals  of  the  first  order;  when  they 
emerge  from  the  first  into  the  second  glands,  secondary 
lacteals,  or  glands  of  the  second  order. 

The  absorbents  of  the  stomach  form  three  divisions: 
one  set  accompanies  the  coronary  artery  and  vein, 
and  enters  the  glands  on  the  lesser  curvature  of  the 
stomach  and  the  omentum  minus.  Those  of  the  second 
set  accompany  the  left  gastro-epiploic  artery,  and  are 
joined  by  the  lymphatics  of  the  omentum.  The  third 
pass  down  upon  the  upper  part  of  the  duodenum,  fol- 
lowing the  arteria  gastro-epiploica  dextra:  these 
descend  to  pass  into  the  same  class  of  glands,  which 
receive  the  lymphatics  of  the  liver.  The  lymphatics 
of  the  stomach  are  joined  in  their  course  by  the  lym- 
phatics of  the  right  side  of  the  omentum. 

The  lacteals  on  the  mesentery  pass  from  one  gland 
to  another,  till  they  form  one  or  two  large  trunks 
only.  These  accompany  the  trunk  of  the  superior 
mesenteric  artery,  and  run  down  on  the  right  side  of 
the  aorta,  and  join  the  thoracic  duct.  The  absorb- 
ents, from  the  rectum  and  colon  of  the  left  side,  pass 
into  their  proper  glands,  or  sometimes  into  the  lumbar 
glands,  and  join  the  thoracic  duct  separately;  those 
from  the  right  side  of  the  colon  join  or  mingle  with 
the  lacteals  in  the  root  of  the  mesentery. 

OF    THE    REMAINING  ABSORBENTS  OF   THE   SOLID 
VISCERA. 

Where  the  lymphatics  of  the  lower  extremity 
descend  over  the  brim  of  the  pelvis,  they  are  joined 
by  the  absorbents  of  the  bladder,  vesiculae  seminales, 
and  other  parts  in  the  pelvis: — small  glands  belonging 
to  this  set,  are  attached  to  the  internal  iliac  vessels. 
In  the  female,  the  lower  set  of  lymphatics,  from  the 


268  LONDON    DISSECTOR,  OR 

womb  and  vagina,  also  come  by  this  route  to  join  those 
of  the  lower  extremity,  or  run  mingling  with  them. 
Another  set  of  lymphatics  of  the  womb  pass  up  with 
the  spermatic  vessels. 

The  lymphatics  of  the  TESTICLE  are  very  numerous. 
They  come  in  distinct  sets  from  the  body  of  the  tes- 
ticle, from  the  epidydimis,  and  from  the  tunica  vagi- 
nalis:  then  reaching  the  cord,  from  six  or  ten  trunks, 
and  run  up  direct  to  the  abdominal  ring;  passing  the 
ring,  they  turn  outward,  and  then  pass  over  the  psoas 
muscle  and  into  the  lumbar  glands. 

The  lymphatics  of  the  KIDNEY  are  in  two  sets, 
superficial  and  deep-seated;  but  the  former  are  seldom 
to  be  observed.  Sometimes  disease  makes  them 
distinct.  The  internal  lymphatics  are  demonstrated 
by  blowing  into  the  veins,  or  tying  a  ligature  and 
kneading  the  substance  of  the  kidney  with  the  fingers; 
when  they  rise,  they  are  seen  attached  to  the  emul- 
gent  vessels,  and  go  to  join  the  lumbar  glands,  or  ter- 
minate in  large  lymphatics  near  the  aorta. 

It  is  needless  to  repeat  that  the  absorbents  of  the 
spleen  are  deep  and  superficial, — for  this  arrangement 
is  general  in  the  solid  viscera.  Emerging  from  the 
spleen,  the  lymphatics  pass  along  the  splenic  vessels, 
and  enter  into  glands  attached  to  the  splenic  artery 
in  its  whole  course.  In  this  course  they  receive  the 
absorbents  from  the  pancreas,  and  near  the  head  of 
the  pancreas  they  are  joined  with  those  of  the  liver, 
and  with  them  enter  into  the  thoracic  duct. 

The  lymphatics  of  the  liver  are  the  most  easily 
detected,  and  they  may  be  injected  to  greater  minute- 
ness, than  any  other  lymphatics  of  the  body.  Although 
they  have  many  valves,  yet  they  do  not  seem  to  close 
the  vessels  entirely,  nor  interrupt  the  mercury  from 
passing  from  trunk  to  branch.  The  superficial  lym- 
phatics, which  are  so  numerous  that  we  may  sometimes 
see  the  mercury  in  them  covering  completely  and  ob- 


GUIDE    TO    ANATOMY.  269 

souring  a  considerable  part  of  the  liver,  have  free 
communication  with  the  internal  set  of  vessels,  which 
are  also  numerous  and  large.  The  principal  route  of 
the  lymphatics  of  the  upper  surface  of  the  liver,  is  by 
the  broad  ligament:  these  perforating  the  diaphragm, 
join  the  trunk,  which  we  have  noticed  under  the  sternum, 
and  in  the  anterior  mediastinum.  It  would  appear,  how- 
ever, that  these  lymphatics  of  the  broad  or  suspensory 
ligament,  are  by  no  means  constant  and  uniform  in  their 
course:  for  sometimes  they  run  down  towards  the 
lateral  ligament,  and  perforate  it  there;  sometimes 
they  pass  down  into  the  thoracic  duct  while  still  in 
the  belly.  While  other  lymphatics  of  great  size  run 
off  from  the  convex  surface  of  the  liver  upon  the  lat- 
eral ligaments,  and  pierce  the  diaphragm  there.  The 
lymphatics  on  the  lower  or  concave  surface  of  the 
liver  are  more  irregular  than  those  of  the  convex 
side.  They  unite  with  the  deep  lymphatics  coming 
out  of  the  porta  along  with  the  vena  portae,  enter  into 
the  glands,  which  are  seated  on  the  trunk  of  that 
vessel,  and  join  the  thoracic  duct  near  the  root  of  the 
superior  mesenteric  artery. 

The  lymphatics  of  the  LUNGS  are  nearly  as  nume- 
rous as  those  of  the  liver;  but,  indeed,  it  is  more  in 
relation  to  the  facility  of  injecting  and  demonstrating 
the  lymphatics,  than  to  their  comparative  number, 
that  we  speak  of  them  in  this  manner.  For  example, 
if  the  lymphatics  of  the  other  viscera  could  be  injected 
to  as  great  minuteness  as  those  of  the  liver,  we  should 
cease  to  consider  that  viscus  as  more  abundantly 
supplied  than  other  parts.  The  superficial  lymphatics 
of  the  lungs  form  areolae,  and  cover  the  surface  almost 
completely.  They  take  a  course  to  the  root  of  the 
lungs,  where  they  are  joined  by  the  deep-seated  ves- 
sels, and  together  pass  into  the  bronchial  glands,  and 
here  the  lymphatics  of  both  sides  freely  communicate. 

The  glands  of  the  lungs  are  constantly  found  both 
24* 


270  LONDON    DISSECTOR,  OR 

before  and  behind  the  bifurcation  of  the  trachea; 
often  these  glands  are  of  a  very  dark  color,  nay,  their 
substance  is  often  found  resolved,  as  it  were,  into  a 
sac  of  ink-like  fluid.  Upon  the  arch  of  the  aorta 
and  the  root  of  the  great  branches  are  the  CARDIAC 
GLANDS,  which  receive  the  lymphatics  from  the  heart. 
The  absorbents  from  the  heart  are  small,  but  very 
numerous,  and  their  larger  branches  attach  themselves 
to  the  coronary  vessels;  they  then  pass  to  the  cardiac 
glands  and  unite  with  the  lymphatics  which  come 
from  the  lungs,  and  so  join  the  thoracic  duct. 


DIRECTIONS    FOR    MAKING    LYM- 
PHATIC  PREPARATIONS. 

GENERAL  OBSERVATIONS. 

1 .  The  part  should  always  be  injected  in  a  proper 
tray,  that  the  mercury  with  which  the  lymphatics  are 
to  be  filled,  may  be  easily  collected. 

2.  A  lancet,  with  a  curved  needle  ready  threaded, 
should  be  always  at  hand. 

3.  A  bottle,  whose  neck  is  not  so  wide  as  to  permit 
the  quicksilver  tube  going  to  the  bottom,  when  placed 
in  it. 

4.  When  injecting,  if  any  circumstance  renders  it 
necessary  for  the  injector  to  put  aside  the  tube  with 
the  mercury,  it  should  be  placed  in  the  bottle,  the 
mercury  remaining  in  it,  to  be  convenient,  and  to  pre- 
vent delay. 

5.  Injecting  with  mercury  is  always  tedious,  and 
frequently  unsuccessful.     The  parts  exposed  must  be 
kept  moist,  by  sprinkling  them  with  cold  water. 


GUIDE    TO    ANATOMY.  271 


A  SUPERIOR  EXTREMITY. 

To  inject  the  lymphatics  of  an  arm,  choose  one  from 
a  dropsical  subject,  without  fat;  make  an  incision  into 
the  skin  around  the  wrist,  and  seek  diligently,  with  a 
magnifying  glass,  for  an  absorbent,  into  which  the  pipe 
is  to  be  put,  when  the  quicksilver  will  immediately  run. 
The  shoulder  should  now  be  placed  considerably  lower 
than  the  hand;  and,  when  the  mercury  runs  out  at 
the  divided  vessels  in  the  axilla,  tie  them  up,  and  also 
the  lymphatic,  into  which  the  pipe  was  introduced. 
Then  seek  for  another  absorbent.  When  the  mer- 
cury ceases  to  run  in  a  lymphatic,  tie  the  vessel,  and 
seek  for  another. 

Dissection.  Begin  at  the  lymphatics  where  the 
mercury  entered,  and  trace  them;  removing  every 
thing  that  obstructs  their  view,  but  preserve  the  glands. 

AN    INFERIOR   EXTREMITY. 

The  limb  for  this  purpose  should  also  be  taken 
from  a  dropsical  person,  and  the  same  method  adopt- 
ed as  with  the  superior  extremity,  seeking  as  near  to 
the  toes  as  possible  for  the  lymphatics. 

A  PAROTID  GLAND. 

Cut  down  upon  the  masseter  muscle,  and  seek  for 
the  Stenonian  duct,  which  is  the  excretory  duct  of 
the  parotid.  Tie  the  quicksilver  pipe  in  it,  then  fix 
the  tube,  and  pour  into  it  the  quicksilver;  and,  when 
it  ceases  to  run,  remove  the  tube  and  pipe,  and  tie 
the  duct.  Be  particularly  careful,  in  dissecting  away 
the  gland,  not  to  cut  it. 

Preservation.  Dry  it  on  a  waxed  board,  and  pre- 
serve it  on  a  blue  paper  and  pasteboard,  in  spirit  of 
turpentine. 


212  LONDON    DISSECTOR.    OR 


LIVER. 

The  lymphatics  running  on  the  peritoneal  coat  of 
the  liver,  and  over  the  gall  bladder,  make  a  beautiful 
preparation.  The  liver  should  be  well  soaked  for 
several  days,  and  the  pipe  put  into  the  lymphatics  of 
the  suspensory  and  coronary  ligaments,  and  the  mer- 
cury forced  along  them,  breaking  down  the  valves 
with  the  nail,  by  pressing  on  the  mercury.  Secure 
the  vessels  at  the  portae  of  the  liver,  when  the  mer- 
cury gets  there,  and  tie  the  lymphatics  when  filled. 
Should  the  anatomist's  attempt  to  force  the  quicksil- 
ver beyond  the  valves  be  unsuccessful,  he  must  fix 
upon  the  most  minute  obvious  branch,  and  let  it  run 
its  proper  course. 

Preservation.  Throw  some  coarse  injection  into 
the  cavae  hepaticas  and  vena  portae,  without  heating 
the  liver  thoroughly;  inflate  the  gall  bladder,  and  dry 
the  whole.  Varnish  it,  and  preserve  it  in  the  best 
manner  under  a  glass  bell,  or  preserve  the  injected  part 
in  proof  spirit,  without  any  wax  injection. 

LUNGS. 

The  superficial  lymphatics  of  the  lungs  are  to  be 
filled  from  the  part  most  remote  from  the  root  of  the 
lungs. 

Preservation.  Cut  away  the  part  on  which  the 
lymphatics  are  filled.  Dry  it  on  a  waxed  board,  var- 
nish it,  and  preserve  it  in  a  bottle,  on  a  green  or  blue 
piece  of  paper;  or  preserve  it  in  proof  spirit,  without 
drying  it. 

HAND. 

Select  the  hand  of  an  aged  female  (separated  from 
the  arm  by  a  transverse  section,  three  inches  above 
the  wrist,)  that  has  died  of  a  lingering  disease.  Soak 


GUIDE    TO    ANATOMY.  273 

out  the  blood  in  warm  water;  fix  the  pipe  in  the  rad- 
ial artery,  then  add  the  tube,  and  pour  into  it  the 
mercury.  As  the  mercury  appears  in  the  other  arte- 
ries and  veins,  take  them  up  and  secure  them  with 
ligatures.  Should  the  mercury  still  escape  from  small 
branches,  put  a  cord  round  the  arm,  and  with  a  piece 
of  wood  tighten  it,  by  twisting  the  cord,  taking  care 
not  to  prevent  the  mercury  passing  into  the  hand. 
Then  suspend  the  hand  in  a  glass  filled  with  water, 
and  suspend  also  the  tube  and  quicksilver,  for  a  day 
or  two,  that  the  mercury  may  get  into  the  small  ves- 
sels. When  injected,  remove  the  pipe,  and  tie,  by  a 
strong  string,  the  fore-arm;  put  the  hand  into  water, 
until  putrefaction  separates  the  cuticle. 

Preservation.  Dry  it  carefully,  and  varnish  it; 
then  fix  the  fore-arm  in  a  pedestal  of  plaister  of  Paris, 
and  keep  the  preparation  under  a  glass  bell. 

LACTEALS. 

Remove  the  mesentery  and  intestines,  if  the  former 
be  perfectly  free  from  fat,  and  let  them  remain  seve- 
ral days  in  water,  which  should  be  frequently  chang- 
ed. Search  for  an  absorbent,  on  the  intestine,  into 
which  introduce  the  quicksilver,  which  will  run  on 
to  the  glands  in  the  mesentery,  where  it  will  stop. 
When  the  lacteals  are  filled,  the  preparation  will  be 
improved  by  injecting  the  mesenteric  arteries  and 
veins  with  red  and  yellow  matter. 

Preservation.  Spread  the  mesentery  on  a  waxed 
board,  inflate  a  portion  of  the  intestine,  remove  all 
that  is  useless;  dry  and  varnish,  and  preserve  it  in  a 
glass  frame. 

FIN  IS. 


